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[PATCH v4 1/1] remove toast reloptions
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* [PATCH v4 1/1] remove toast reloptions
@ 2026-04-07 20:30 Nathan Bossart <nathan@postgresql.org>
  0 siblings, 0 replies; 332+ messages in thread

From: Nathan Bossart @ 2026-04-07 20:30 UTC (permalink / raw)

---
 doc/src/sgml/ref/create_table.sgml            | 51 ++++++-------
 src/backend/access/common/reloptions.c        | 49 +++++-------
 src/backend/catalog/toasting.c                | 31 ++++----
 src/backend/commands/createas.c               | 13 +---
 src/backend/commands/repack.c                 | 15 +---
 src/backend/commands/tablecmds.c              | 19 +----
 src/backend/commands/vacuum.c                 | 14 +---
 src/backend/postmaster/autovacuum.c           | 48 +++++-------
 src/backend/tcop/utility.c                    | 19 +----
 src/bin/pg_upgrade/check.c                    | 75 +++++++++++++++++++
 src/include/access/reloptions.h               | 24 +++---
 src/include/catalog/toasting.h                |  6 +-
 .../injection_points/expected/vacuum.out      | 24 +++---
 .../modules/injection_points/sql/vacuum.sql   | 20 ++---
 src/test/regress/expected/alter_table.out     |  9 ---
 src/test/regress/expected/reloptions.out      | 56 ++------------
 src/test/regress/expected/vacuum.out          |  8 --
 src/test/regress/sql/alter_table.sql          |  4 -
 src/test/regress/sql/reloptions.sql           | 32 +-------
 src/test/regress/sql/vacuum.sql               |  8 --
 20 files changed, 199 insertions(+), 326 deletions(-)

diff --git a/doc/src/sgml/ref/create_table.sgml b/doc/src/sgml/ref/create_table.sgml
index e342585c7f0..b8d2a657d10 100644
--- a/doc/src/sgml/ref/create_table.sgml
+++ b/doc/src/sgml/ref/create_table.sgml
@@ -1589,14 +1589,10 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
     Storage parameters for
     indexes are documented in <xref linkend="sql-createindex"/>.
     The storage parameters currently
-    available for tables are listed below.  For many of these parameters, as
-    shown, there is an additional parameter with the same name prefixed with
-    <literal>toast.</literal>, which controls the behavior of the
+    available for tables are listed below.  Unless otherwise noted, a table's
+    parameter value also controls the behavior of the
     table's secondary <acronym>TOAST</acronym> table, if any
     (see <xref linkend="storage-toast"/> for more information about TOAST).
-    If a table parameter value is set and the
-    equivalent <literal>toast.</literal> parameter is not, the TOAST table
-    will use the table's parameter value.
     Specifying these parameters for partitioned tables is not supported,
     but you may specify them for individual leaf partitions.
    </para>
@@ -1622,7 +1618,8 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
       updates</link> more likely.
       For a table whose entries are never updated, complete packing is the
       best choice, but in heavily updated tables smaller fillfactors are
-      appropriate.  This parameter cannot be set for TOAST tables.
+      appropriate.  This parameter does not affect the table's secondary TOAST
+      table.
      </para>
     </listitem>
    </varlistentry>
@@ -1648,7 +1645,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
       Note that the default setting is often close to optimal, and
       it is possible that setting this parameter could have negative
       effects in some cases.
-      This parameter cannot be set for TOAST tables.
+      This parameter does not affect the table's secondary TOAST table.
      </para>
     </listitem>
    </varlistentry>
@@ -1671,7 +1668,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-enabled" xreflabel="autovacuum_enabled">
-    <term><literal>autovacuum_enabled</literal>, <literal>toast.autovacuum_enabled</literal> (<type>boolean</type>)
+    <term><literal>autovacuum_enabled</literal> (<type>boolean</type>)
     <indexterm>
      <primary><varname>autovacuum_enabled</varname> storage parameter</primary>
     </indexterm>
@@ -1696,7 +1693,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-vacuum-index-cleanup" xreflabel="vacuum_index_cleanup">
-    <term><literal>vacuum_index_cleanup</literal>, <literal>toast.vacuum_index_cleanup</literal> (<type>enum</type>)
+    <term><literal>vacuum_index_cleanup</literal> (<type>enum</type>)
     <indexterm>
      <primary><varname>vacuum_index_cleanup</varname> storage parameter</primary>
     </indexterm>
@@ -1722,7 +1719,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-vacuum-truncate" xreflabel="vacuum_truncate">
-    <term><literal>vacuum_truncate</literal>, <literal>toast.vacuum_truncate</literal> (<type>boolean</type>)
+    <term><literal>vacuum_truncate</literal> (<type>boolean</type>)
     <indexterm>
      <primary><varname>vacuum_truncate</varname></primary>
      <secondary>storage parameter</secondary>
@@ -1755,7 +1752,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-vacuum-threshold" xreflabel="autovacuum_vacuum_threshold">
-    <term><literal>autovacuum_vacuum_threshold</literal>, <literal>toast.autovacuum_vacuum_threshold</literal> (<type>integer</type>)
+    <term><literal>autovacuum_vacuum_threshold</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_vacuum_threshold</varname></primary>
      <secondary>storage parameter</secondary>
@@ -1770,7 +1767,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-vacuum-max-threshold" xreflabel="autovacuum_vacuum_max_threshold">
-    <term><literal>autovacuum_vacuum_max_threshold</literal>, <literal>toast.autovacuum_vacuum_max_threshold</literal> (<type>integer</type>)
+    <term><literal>autovacuum_vacuum_max_threshold</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_vacuum_max_threshold</varname></primary>
      <secondary>storage parameter</secondary>
@@ -1785,7 +1782,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
   </varlistentry>
 
    <varlistentry id="reloption-autovacuum-vacuum-scale-factor" xreflabel="autovacuum_vacuum_scale_factor">
-    <term><literal>autovacuum_vacuum_scale_factor</literal>, <literal>toast.autovacuum_vacuum_scale_factor</literal> (<type>floating point</type>)
+    <term><literal>autovacuum_vacuum_scale_factor</literal> (<type>floating point</type>)
     <indexterm>
      <primary><varname>autovacuum_vacuum_scale_factor</varname> </primary>
      <secondary>storage parameter</secondary>
@@ -1800,7 +1797,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-vacuum-insert-threshold" xreflabel="autovacuum_vacuum_insert_threshold">
-    <term><literal>autovacuum_vacuum_insert_threshold</literal>, <literal>toast.autovacuum_vacuum_insert_threshold</literal> (<type>integer</type>)
+    <term><literal>autovacuum_vacuum_insert_threshold</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_vacuum_insert_threshold</varname></primary>
      <secondary>storage parameter</secondary>
@@ -1815,7 +1812,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-vacuum-insert-scale-factor" xreflabel="autovacuum_vacuum_insert_scale_factor">
-    <term><literal>autovacuum_vacuum_insert_scale_factor</literal>, <literal>toast.autovacuum_vacuum_insert_scale_factor</literal> (<type>floating point</type>)
+    <term><literal>autovacuum_vacuum_insert_scale_factor</literal> (<type>floating point</type>)
     <indexterm>
      <primary><varname>autovacuum_vacuum_insert_scale_factor</varname> </primary>
      <secondary>storage parameter</secondary>
@@ -1860,7 +1857,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-vacuum-cost-delay" xreflabel="autovacuum_vacuum_cost_delay">
-    <term><literal>autovacuum_vacuum_cost_delay</literal>, <literal>toast.autovacuum_vacuum_cost_delay</literal> (<type>floating point</type>)
+    <term><literal>autovacuum_vacuum_cost_delay</literal> (<type>floating point</type>)
     <indexterm>
      <primary><varname>autovacuum_vacuum_cost_delay</varname></primary>
      <secondary>storage parameter</secondary>
@@ -1875,7 +1872,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-vacuum-cost-limit" xreflabel="autovacuum_vacuum_cost_limit">
-    <term><literal>autovacuum_vacuum_cost_limit</literal>, <literal>toast.autovacuum_vacuum_cost_limit</literal> (<type>integer</type>)
+    <term><literal>autovacuum_vacuum_cost_limit</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_vacuum_cost_limit</varname></primary>
      <secondary>storage parameter</secondary>
@@ -1890,7 +1887,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-freeze-min-age" xreflabel="autovacuum_freeze_min_age">
-    <term><literal>autovacuum_freeze_min_age</literal>, <literal>toast.autovacuum_freeze_min_age</literal> (<type>integer</type>)
+    <term><literal>autovacuum_freeze_min_age</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_freeze_min_age</varname> storage parameter</primary>
     </indexterm>
@@ -1907,7 +1904,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-freeze-max-age" xreflabel="autovacuum_freeze_max_age">
-    <term><literal>autovacuum_freeze_max_age</literal>, <literal>toast.autovacuum_freeze_max_age</literal> (<type>integer</type>)
+    <term><literal>autovacuum_freeze_max_age</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_freeze_max_age</varname></primary>
      <secondary>storage parameter</secondary>
@@ -1924,7 +1921,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-freeze-table-age" xreflabel="autovacuum_freeze_table_age">
-    <term><literal>autovacuum_freeze_table_age</literal>, <literal>toast.autovacuum_freeze_table_age</literal> (<type>integer</type>)
+    <term><literal>autovacuum_freeze_table_age</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_freeze_table_age</varname> storage parameter</primary>
     </indexterm>
@@ -1938,7 +1935,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-multixact-freeze-min-age" xreflabel="autovacuum_multixact_freeze_min_age">
-    <term><literal>autovacuum_multixact_freeze_min_age</literal>, <literal>toast.autovacuum_multixact_freeze_min_age</literal> (<type>integer</type>)
+    <term><literal>autovacuum_multixact_freeze_min_age</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_multixact_freeze_min_age</varname> storage parameter</primary>
     </indexterm>
@@ -1956,7 +1953,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-multixact-freeze-max-age" xreflabel="autovacuum_multixact_freeze_max_age">
-    <term><literal>autovacuum_multixact_freeze_max_age</literal>, <literal>toast.autovacuum_multixact_freeze_max_age</literal> (<type>integer</type>)
+    <term><literal>autovacuum_multixact_freeze_max_age</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_multixact_freeze_max_age</varname></primary>
      <secondary>storage parameter</secondary>
@@ -1975,7 +1972,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-autovacuum-multixact-freeze-table-age" xreflabel="autovacuum_multixact_freeze_table_age">
-    <term><literal>autovacuum_multixact_freeze_table_age</literal>, <literal>toast.autovacuum_multixact_freeze_table_age</literal> (<type>integer</type>)
+    <term><literal>autovacuum_multixact_freeze_table_age</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>autovacuum_multixact_freeze_table_age</varname> storage parameter</primary>
     </indexterm>
@@ -1989,7 +1986,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-log-autovacuum-min-duration" xreflabel="log_autovacuum_min_duration">
-    <term><literal>log_autovacuum_min_duration</literal>, <literal>toast.log_autovacuum_min_duration</literal> (<type>integer</type>)
+    <term><literal>log_autovacuum_min_duration</literal> (<type>integer</type>)
     <indexterm>
      <primary><varname>log_autovacuum_min_duration</varname></primary>
      <secondary>storage parameter</secondary>
@@ -2019,7 +2016,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
    </varlistentry>
 
    <varlistentry id="reloption-vacuum-max-eager-freeze-failure-rate" xreflabel="vacuum_max_eager_freeze_failure_rate">
-    <term><literal>vacuum_max_eager_freeze_failure_rate</literal>, <literal>toast.vacuum_max_eager_freeze_failure_rate</literal> (<type>floating point</type>)
+    <term><literal>vacuum_max_eager_freeze_failure_rate</literal> (<type>floating point</type>)
     <indexterm>
      <primary><varname>vacuum_max_eager_freeze_failure_rate</varname></primary>
      <secondary>storage parameter</secondary>
@@ -2044,7 +2041,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
       Declare the table as an additional catalog table for purposes of
       logical replication. See
       <xref linkend="logicaldecoding-capabilities"/> for details.
-      This parameter cannot be set for TOAST tables.
+      This parameter does not affect the table's secondary TOAST table.
      </para>
     </listitem>
    </varlistentry>
diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 3e832c3797e..50d9805f3d8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -111,7 +111,7 @@ static relopt_bool boolRelOpts[] =
 		{
 			"autovacuum_enabled",
 			"Enables autovacuum in this relation",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		true
@@ -172,7 +172,7 @@ static relopt_ternary ternaryRelOpts[] =
 		{
 			"vacuum_truncate",
 			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		}
 	},
@@ -249,7 +249,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_vacuum_threshold",
 			"Minimum number of tuple updates or deletes prior to vacuum",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 0, INT_MAX
@@ -258,7 +258,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_vacuum_max_threshold",
 			"Maximum number of tuple updates or deletes prior to vacuum",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-2, -1, INT_MAX
@@ -267,7 +267,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_vacuum_insert_threshold",
 			"Minimum number of tuple inserts prior to vacuum, or -1 to disable insert vacuums",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-2, -1, INT_MAX
@@ -285,7 +285,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_vacuum_cost_limit",
 			"Vacuum cost amount available before napping, for autovacuum",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 1, 10000
@@ -294,7 +294,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_freeze_min_age",
 			"Minimum age at which VACUUM should freeze a table row, for autovacuum",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 0, 1000000000
@@ -303,7 +303,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_multixact_freeze_min_age",
 			"Minimum multixact age at which VACUUM should freeze a row multixact's, for autovacuum",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 0, 1000000000
@@ -312,7 +312,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_freeze_max_age",
 			"Age at which to autovacuum a table to prevent transaction ID wraparound",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 100000, 2000000000
@@ -321,7 +321,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_multixact_freeze_max_age",
 			"Multixact age at which to autovacuum a table to prevent multixact wraparound",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 10000, 2000000000
@@ -330,7 +330,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_freeze_table_age",
 			"Age at which VACUUM should perform a full table sweep to freeze row versions",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		}, -1, 0, 2000000000
 	},
@@ -338,7 +338,7 @@ static relopt_int intRelOpts[] =
 		{
 			"autovacuum_multixact_freeze_table_age",
 			"Age of multixact at which VACUUM should perform a full table sweep to freeze row versions",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		}, -1, 0, 2000000000
 	},
@@ -346,7 +346,7 @@ static relopt_int intRelOpts[] =
 		{
 			"log_autovacuum_min_duration",
 			"Sets the minimum execution time above which vacuum actions by autovacuum will be logged",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, -1, INT_MAX
@@ -424,7 +424,7 @@ static relopt_real realRelOpts[] =
 		{
 			"autovacuum_vacuum_cost_delay",
 			"Vacuum cost delay in milliseconds, for autovacuum",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 0.0, 100.0
@@ -433,7 +433,7 @@ static relopt_real realRelOpts[] =
 		{
 			"autovacuum_vacuum_scale_factor",
 			"Number of tuple updates or deletes prior to vacuum as a fraction of reltuples",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 0.0, 100.0
@@ -442,7 +442,7 @@ static relopt_real realRelOpts[] =
 		{
 			"autovacuum_vacuum_insert_scale_factor",
 			"Number of tuple inserts prior to vacuum as a fraction of reltuples",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 0.0, 100.0
@@ -460,7 +460,7 @@ static relopt_real realRelOpts[] =
 		{
 			"vacuum_max_eager_freeze_failure_rate",
 			"Fraction of pages in a relation vacuum can scan and fail to freeze before disabling eager scanning.",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		-1, 0.0, 1.0
@@ -554,7 +554,7 @@ static relopt_enum enumRelOpts[] =
 		{
 			"vacuum_index_cleanup",
 			"Controls index vacuuming and index cleanup",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			RELOPT_KIND_HEAP,
 			ShareUpdateExclusiveLock
 		},
 		StdRdOptIndexCleanupValues,
@@ -2163,21 +2163,8 @@ view_reloptions(Datum reloptions, bool validate)
 bytea *
 heap_reloptions(char relkind, Datum reloptions, bool validate)
 {
-	StdRdOptions *rdopts;
-
 	switch (relkind)
 	{
-		case RELKIND_TOASTVALUE:
-			rdopts = (StdRdOptions *)
-				default_reloptions(reloptions, validate, RELOPT_KIND_TOAST);
-			if (rdopts != NULL)
-			{
-				/* adjust default-only parameters for TOAST relations */
-				rdopts->fillfactor = 100;
-				rdopts->autovacuum.analyze_threshold = -1;
-				rdopts->autovacuum.analyze_scale_factor = -1;
-			}
-			return (bytea *) rdopts;
 		case RELKIND_RELATION:
 		case RELKIND_MATVIEW:
 			return default_reloptions(reloptions, validate, RELOPT_KIND_HEAP);
diff --git a/src/backend/catalog/toasting.c b/src/backend/catalog/toasting.c
index 4aa52a4bd25..9f1f822702c 100644
--- a/src/backend/catalog/toasting.c
+++ b/src/backend/catalog/toasting.c
@@ -34,11 +34,11 @@
 #include "utils/rel.h"
 #include "utils/syscache.h"
 
-static void CheckAndCreateToastTable(Oid relOid, Datum reloptions,
+static void CheckAndCreateToastTable(Oid relOid,
 									 LOCKMODE lockmode, bool check,
 									 Oid OIDOldToast);
 static bool create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid,
-							   Datum reloptions, LOCKMODE lockmode, bool check,
+							   LOCKMODE lockmode, bool check,
 							   Oid OIDOldToast);
 static bool needs_toast_table(Relation rel);
 
@@ -48,35 +48,30 @@ static bool needs_toast_table(Relation rel);
  *		If the table needs a toast table, and doesn't already have one,
  *		then create a toast table for it.
  *
- * reloptions for the toast table can be passed, too.  Pass (Datum) 0
- * for default reloptions.
- *
  * We expect the caller to have verified that the relation is a table and have
  * already done any necessary permission checks.  Callers expect this function
  * to end with CommandCounterIncrement if it makes any changes.
  */
 void
-AlterTableCreateToastTable(Oid relOid, Datum reloptions, LOCKMODE lockmode)
+AlterTableCreateToastTable(Oid relOid, LOCKMODE lockmode)
 {
-	CheckAndCreateToastTable(relOid, reloptions, lockmode, true, InvalidOid);
+	CheckAndCreateToastTable(relOid, lockmode, true, InvalidOid);
 }
 
 void
-NewHeapCreateToastTable(Oid relOid, Datum reloptions, LOCKMODE lockmode,
-						Oid OIDOldToast)
+NewHeapCreateToastTable(Oid relOid, LOCKMODE lockmode, Oid OIDOldToast)
 {
-	CheckAndCreateToastTable(relOid, reloptions, lockmode, false, OIDOldToast);
+	CheckAndCreateToastTable(relOid, lockmode, false, OIDOldToast);
 }
 
 void
-NewRelationCreateToastTable(Oid relOid, Datum reloptions)
+NewRelationCreateToastTable(Oid relOid)
 {
-	CheckAndCreateToastTable(relOid, reloptions, AccessExclusiveLock, false,
-							 InvalidOid);
+	CheckAndCreateToastTable(relOid, AccessExclusiveLock, false, InvalidOid);
 }
 
 static void
-CheckAndCreateToastTable(Oid relOid, Datum reloptions, LOCKMODE lockmode,
+CheckAndCreateToastTable(Oid relOid, LOCKMODE lockmode,
 						 bool check, Oid OIDOldToast)
 {
 	Relation	rel;
@@ -84,7 +79,7 @@ CheckAndCreateToastTable(Oid relOid, Datum reloptions, LOCKMODE lockmode,
 	rel = table_open(relOid, lockmode);
 
 	/* create_toast_table does all the work */
-	(void) create_toast_table(rel, InvalidOid, InvalidOid, reloptions, lockmode,
+	(void) create_toast_table(rel, InvalidOid, InvalidOid, lockmode,
 							  check, OIDOldToast);
 
 	table_close(rel, NoLock);
@@ -108,7 +103,7 @@ BootstrapToastTable(char *relName, Oid toastOid, Oid toastIndexOid)
 			 relName);
 
 	/* create_toast_table does all the work */
-	if (!create_toast_table(rel, toastOid, toastIndexOid, (Datum) 0,
+	if (!create_toast_table(rel, toastOid, toastIndexOid,
 							AccessExclusiveLock, false, InvalidOid))
 		elog(ERROR, "\"%s\" does not require a toast table",
 			 relName);
@@ -126,7 +121,7 @@ BootstrapToastTable(char *relName, Oid toastOid, Oid toastIndexOid)
  */
 static bool
 create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid,
-				   Datum reloptions, LOCKMODE lockmode, bool check,
+				   LOCKMODE lockmode, bool check,
 				   Oid OIDOldToast)
 {
 	Oid			relOid = RelationGetRelid(rel);
@@ -266,7 +261,7 @@ create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid,
 										   shared_relation,
 										   mapped_relation,
 										   ONCOMMIT_NOOP,
-										   reloptions,
+										   (Datum) 0,
 										   false,
 										   true,
 										   true,
diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c
index 6dbb831ca89..188e167999b 100644
--- a/src/backend/commands/createas.c
+++ b/src/backend/commands/createas.c
@@ -84,8 +84,6 @@ create_ctas_internal(List *attrList, IntoClause *into)
 	CreateStmt *create = makeNode(CreateStmt);
 	bool		is_matview;
 	char		relkind;
-	Datum		toast_options;
-	const char *const validnsps[] = HEAP_RELOPT_NAMESPACES;
 	ObjectAddress intoRelationAddr;
 
 	/* This code supports both CREATE TABLE AS and CREATE MATERIALIZED VIEW */
@@ -120,16 +118,7 @@ create_ctas_internal(List *attrList, IntoClause *into)
 	 */
 	CommandCounterIncrement();
 
-	/* parse and validate reloptions for the toast table */
-	toast_options = transformRelOptions((Datum) 0,
-										create->options,
-										"toast",
-										validnsps,
-										true, false);
-
-	(void) heap_reloptions(RELKIND_TOASTVALUE, toast_options, true);
-
-	NewRelationCreateToastTable(intoRelationAddr.objectId, toast_options);
+	NewRelationCreateToastTable(intoRelationAddr.objectId);
 
 	/* Create the "view" part of a materialized view. */
 	if (is_matview)
diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index 9a199dd9bfb..3b80d331815 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -1201,20 +1201,7 @@ make_new_heap(Oid OIDOldHeap, Oid NewTableSpace, Oid NewAccessMethod,
 	 */
 	toastid = OldHeap->rd_rel->reltoastrelid;
 	if (OidIsValid(toastid))
-	{
-		/* keep the existing toast table's reloptions, if any */
-		tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(toastid));
-		if (!HeapTupleIsValid(tuple))
-			elog(ERROR, "cache lookup failed for relation %u", toastid);
-		reloptions = SysCacheGetAttr(RELOID, tuple, Anum_pg_class_reloptions,
-									 &isNull);
-		if (isNull)
-			reloptions = (Datum) 0;
-
-		NewHeapCreateToastTable(OIDNewHeap, reloptions, lockmode, toastid);
-
-		ReleaseSysCache(tuple);
-	}
+		NewHeapCreateToastTable(OIDNewHeap, lockmode, toastid);
 
 	table_close(OldHeap, NoLock);
 
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index d8d7969bf30..a254509cbb5 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -827,7 +827,6 @@ DefineRelation(CreateStmt *stmt, char relkind, Oid ownerId,
 	ListCell   *listptr;
 	AttrNumber	attnum;
 	bool		partitioned;
-	const char *const validnsps[] = HEAP_RELOPT_NAMESPACES;
 	Oid			ofTypeId;
 	ObjectAddress address;
 	LOCKMODE	parentLockmode;
@@ -976,7 +975,7 @@ DefineRelation(CreateStmt *stmt, char relkind, Oid ownerId,
 	/*
 	 * Parse and validate reloptions, if any.
 	 */
-	reloptions = transformRelOptions((Datum) 0, stmt->options, NULL, validnsps,
+	reloptions = transformRelOptions((Datum) 0, stmt->options, NULL, NULL,
 									 true, false);
 
 	switch (relkind)
@@ -5433,7 +5432,7 @@ ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode,
 			  tab->relkind == RELKIND_PARTITIONED_TABLE) &&
 			 tab->partition_constraint == NULL) ||
 			tab->relkind == RELKIND_MATVIEW)
-			AlterTableCreateToastTable(tab->relid, (Datum) 0, lockmode);
+			AlterTableCreateToastTable(tab->relid, lockmode);
 	}
 }
 
@@ -16927,7 +16926,6 @@ ATExecSetRelOptions(Relation rel, List *defList, AlterTableType operation,
 	Datum		repl_val[Natts_pg_class];
 	bool		repl_null[Natts_pg_class];
 	bool		repl_repl[Natts_pg_class];
-	const char *const validnsps[] = HEAP_RELOPT_NAMESPACES;
 
 	if (defList == NIL && operation != AT_ReplaceRelOptions)
 		return;					/* nothing to do */
@@ -16960,7 +16958,7 @@ ATExecSetRelOptions(Relation rel, List *defList, AlterTableType operation,
 	}
 
 	/* Generate new proposed reloptions (text array) */
-	newOptions = transformRelOptions(datum, defList, NULL, validnsps, false,
+	newOptions = transformRelOptions(datum, defList, NULL, NULL, false,
 									 operation == AT_ResetRelOptions);
 
 	/* Validate */
@@ -17083,20 +17081,11 @@ ATExecSetRelOptions(Relation rel, List *defList, AlterTableType operation,
 				datum = (Datum) 0;
 		}
 
-		newOptions = transformRelOptions(datum, defList, "toast", validnsps,
-										 false, operation == AT_ResetRelOptions);
-
-		(void) heap_reloptions(RELKIND_TOASTVALUE, newOptions, true);
-
 		memset(repl_val, 0, sizeof(repl_val));
 		memset(repl_null, false, sizeof(repl_null));
 		memset(repl_repl, false, sizeof(repl_repl));
 
-		if (newOptions != (Datum) 0)
-			repl_val[Anum_pg_class_reloptions - 1] = newOptions;
-		else
-			repl_null[Anum_pg_class_reloptions - 1] = true;
-
+		repl_null[Anum_pg_class_reloptions - 1] = true;
 		repl_repl[Anum_pg_class_reloptions - 1] = true;
 
 		newtuple = heap_modify_tuple(tuple, RelationGetDescr(pgclass),
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index a4abb29cf64..2b44afdbf25 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2020,13 +2020,6 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	Oid			save_userid;
 	int			save_sec_context;
 	int			save_nestlevel;
-	VacuumParams toast_vacuum_params;
-
-	/*
-	 * This function scribbles on the parameters, so make a copy early to
-	 * avoid affecting the TOAST table (if we do end up recursing to it).
-	 */
-	memcpy(&toast_vacuum_params, &params, sizeof(VacuumParams));
 
 	/* Begin a transaction for vacuuming this relation */
 	StartTransactionCommand();
@@ -2341,11 +2334,10 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 		 * relation.  NB: This is only safe to do because we hold a session
 		 * lock on the main relation that prevents concurrent deletion.
 		 */
-		toast_vacuum_params.options |= VACOPT_PROCESS_MAIN;
-		toast_vacuum_params.toast_parent = relid;
+		params.options |= VACOPT_PROCESS_MAIN;
+		params.toast_parent = relid;
 
-		vacuum_rel(toast_relid, NULL, toast_vacuum_params, bstrategy,
-				   isTopLevel);
+		vacuum_rel(toast_relid, NULL, params, bstrategy, isTopLevel);
 	}
 
 	/*
diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index a5a8db2ff88..c0e7cbf2cb8 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -2139,8 +2139,9 @@ do_autovacuum(void)
 	{
 		Form_pg_class classForm = (Form_pg_class) GETSTRUCT(tuple);
 		Oid			relid;
-		AutoVacOpts *relopts;
-		bool		free_relopts = false;
+		av_relation *hentry;
+		bool		found;
+		AutoVacOpts *relopts = NULL;
 		bool		dovacuum;
 		bool		doanalyze;
 		bool		wraparound;
@@ -2154,22 +2155,10 @@ do_autovacuum(void)
 
 		relid = classForm->oid;
 
-		/*
-		 * fetch reloptions -- if this toast table does not have them, try the
-		 * main rel
-		 */
-		relopts = extract_autovac_opts(tuple, pg_class_desc);
-		if (relopts)
-			free_relopts = true;
-		else
-		{
-			av_relation *hentry;
-			bool		found;
-
-			hentry = hash_search(table_toast_map, &relid, HASH_FIND, &found);
-			if (found && hentry->ar_hasrelopts)
-				relopts = &hentry->ar_reloptions;
-		}
+		/* Use reloptions from main rel. */
+		hentry = hash_search(table_toast_map, &relid, HASH_FIND, &found);
+		if (found && hentry->ar_hasrelopts)
+			relopts = &hentry->ar_reloptions;
 
 		relation_needs_vacanalyze(relid, relopts, classForm,
 								  effective_multixact_freeze_max_age,
@@ -2186,10 +2175,6 @@ do_autovacuum(void)
 			table->score = scores.max;
 			tables_to_process = lappend(tables_to_process, table);
 		}
-
-		/* Release stuff to avoid leakage */
-		if (free_relopts)
-			pfree(relopts);
 	}
 
 	table_endscan(relScan);
@@ -2826,7 +2811,7 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 	bool		doanalyze;
 	autovac_table *tab = NULL;
 	bool		wraparound;
-	AutoVacOpts *avopts;
+	AutoVacOpts *avopts = NULL;
 	bool		free_avopts = false;
 	AutoVacuumScores scores;
 
@@ -2838,13 +2823,15 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 
 	/*
 	 * Get the applicable reloptions.  If it is a TOAST table, try to get the
-	 * main table reloptions if the toast table itself doesn't have.
+	 * main table reloptions.
 	 */
-	avopts = extract_autovac_opts(classTup, pg_class_desc);
-	if (avopts)
-		free_avopts = true;
-	else if (classForm->relkind == RELKIND_TOASTVALUE &&
-			 table_toast_map != NULL)
+	if (classForm->relkind != RELKIND_TOASTVALUE)
+	{
+		avopts = extract_autovac_opts(classTup, pg_class_desc);
+		if (avopts)
+			free_avopts = true;
+	}
+	else if (table_toast_map)
 	{
 		av_relation *hentry;
 		bool		found;
@@ -3127,8 +3114,7 @@ relation_needs_vacanalyze(Oid relid,
 
 	/*
 	 * Determine vacuum/analyze equation parameters.  We have two possible
-	 * sources: the passed reloptions (which could be a main table or a toast
-	 * table), or the autovacuum GUC variables.
+	 * sources: the passed reloptions or the autovacuum GUC variables.
 	 */
 
 	/* -1 in autovac setting means use plain vacuum_scale_factor */
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 73a56f1df1d..d089e02c216 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1159,8 +1159,6 @@ ProcessUtilitySlow(ParseState *pstate,
 						if (IsA(stmt, CreateStmt))
 						{
 							CreateStmt *cstmt = (CreateStmt *) stmt;
-							Datum		toast_options;
-							const char *const validnsps[] = HEAP_RELOPT_NAMESPACES;
 
 							/* Remember transformed RangeVar for LIKE */
 							table_rv = cstmt->relation;
@@ -1180,22 +1178,7 @@ ProcessUtilitySlow(ParseState *pstate,
 							 */
 							CommandCounterIncrement();
 
-							/*
-							 * parse and validate reloptions for the toast
-							 * table
-							 */
-							toast_options = transformRelOptions((Datum) 0,
-																cstmt->options,
-																"toast",
-																validnsps,
-																true,
-																false);
-							(void) heap_reloptions(RELKIND_TOASTVALUE,
-												   toast_options,
-												   true);
-
-							NewRelationCreateToastTable(address.objectId,
-														toast_options);
+							NewRelationCreateToastTable(address.objectId);
 						}
 						else if (IsA(stmt, CreateForeignTableStmt))
 						{
diff --git a/src/bin/pg_upgrade/check.c b/src/bin/pg_upgrade/check.c
index 5a7afe62eab..18d49a6fc17 100644
--- a/src/bin/pg_upgrade/check.c
+++ b/src/bin/pg_upgrade/check.c
@@ -37,6 +37,7 @@ static void check_new_cluster_subscription_configuration(void);
 static void check_old_cluster_for_valid_slots(void);
 static void check_old_cluster_subscription_state(void);
 static void check_old_cluster_global_names(ClusterInfo *cluster);
+static void check_for_toast_reloptions(ClusterInfo *cluster);
 
 /*
  * DataTypesUsageChecks - definitions of data type checks for the old cluster
@@ -634,6 +635,9 @@ check_and_dump_old_cluster(void)
 	check_for_prepared_transactions(&old_cluster);
 	check_for_isn_and_int8_passing_mismatch(&old_cluster);
 
+	if (GET_MAJOR_VERSION(old_cluster.major_version) < 2000)
+		check_for_toast_reloptions(&old_cluster);
+
 	if (GET_MAJOR_VERSION(old_cluster.major_version) >= 1700)
 	{
 		/*
@@ -2644,3 +2648,74 @@ check_old_cluster_global_names(ClusterInfo *cluster)
 	else
 		check_ok();
 }
+
+/*
+ * Callback function for processing results of query for
+ * check_for_toast_reloptions()'s UpgradeTask.  If the query returned any rows
+ * (i.e., the check failed), write the details to the report file.
+ */
+static void
+process_toast_relopts_check(DbInfo *dbinfo, PGresult *res, void *arg)
+{
+	UpgradeTaskReport *report = (UpgradeTaskReport *) arg;
+	int			ntups = PQntuples(res);
+	int			i_nspname = PQfnumber(res, "nspname");
+	int			i_relname = PQfnumber(res, "relname");
+
+	if (ntups == 0)
+		return;
+
+	if (report->file == NULL &&
+		(report->file = fopen_priv(report->path, "w")) == NULL)
+		pg_fatal("could not open file \"%s\": %m", report->path);
+
+	fprintf(report->file, "In database: %s\n", dbinfo->db_name);
+
+	for (int rowno = 0; rowno < ntups; rowno++)
+		fprintf(report->file, "  %s.%s\n",
+				PQgetvalue(res, rowno, i_nspname),
+				PQgetvalue(res, rowno, i_relname));
+}
+
+/*
+ * Verify that no storage parameters (a.k.a. reloptions) are defined for TOAST
+ * tables.
+ */
+static void
+check_for_toast_reloptions(ClusterInfo *cluster)
+{
+	UpgradeTaskReport report;
+	UpgradeTask *task = upgrade_task_create();
+	const char *query = "SELECT n.nspname, c.relname "
+		"FROM  pg_catalog.pg_class c, "
+		"      pg_catalog.pg_class tc, "
+		"      pg_catalog.pg_namespace n "
+		"WHERE c.reltoastrelid = tc.oid AND "
+		"      c.relnamespace = n.oid AND "
+		"      tc.reloptions IS NOT NULL";
+
+	prep_status("Check for tables with TOAST storage parameters");
+
+	report.file = NULL;
+	snprintf(report.path, sizeof(report.path), "%s/%s",
+			 log_opts.basedir,
+			 "tables_with_toast_storage_parameters.txt");
+
+	upgrade_task_add_step(task, query, process_toast_relopts_check,
+						  true, &report);
+	upgrade_task_run(task, cluster);
+	upgrade_task_free(task);
+
+	if (report.file)
+	{
+		fclose(report.file);
+		pg_log(PG_REPORT, "fatal");
+		pg_fatal("Your installation contains tables with TOAST storage parameters set, which is\n"
+				 "not supported anymore.  Consider remove the TOAST storage parameters using\n"
+				 "    ALTER TABLE ... RESET ( ... );\n"
+				 "A list of tables with the problem is in the file:\n"
+				 "    %s", report.path);
+	}
+	else
+		check_ok();
+}
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index e8cb7f7a627..4415c1ca9b5 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -40,26 +40,22 @@ typedef enum relopt_kind
 {
 	RELOPT_KIND_LOCAL = 0,
 	RELOPT_KIND_HEAP = (1 << 0),
-	RELOPT_KIND_TOAST = (1 << 1),
-	RELOPT_KIND_BTREE = (1 << 2),
-	RELOPT_KIND_HASH = (1 << 3),
-	RELOPT_KIND_GIN = (1 << 4),
-	RELOPT_KIND_GIST = (1 << 5),
-	RELOPT_KIND_ATTRIBUTE = (1 << 6),
-	RELOPT_KIND_TABLESPACE = (1 << 7),
-	RELOPT_KIND_SPGIST = (1 << 8),
-	RELOPT_KIND_VIEW = (1 << 9),
-	RELOPT_KIND_BRIN = (1 << 10),
-	RELOPT_KIND_PARTITIONED = (1 << 11),
+	RELOPT_KIND_BTREE = (1 << 1),
+	RELOPT_KIND_HASH = (1 << 2),
+	RELOPT_KIND_GIN = (1 << 3),
+	RELOPT_KIND_GIST = (1 << 4),
+	RELOPT_KIND_ATTRIBUTE = (1 << 5),
+	RELOPT_KIND_TABLESPACE = (1 << 6),
+	RELOPT_KIND_SPGIST = (1 << 7),
+	RELOPT_KIND_VIEW = (1 << 8),
+	RELOPT_KIND_BRIN = (1 << 9),
+	RELOPT_KIND_PARTITIONED = (1 << 10),
 	/* if you add a new kind, make sure you update "last_default" too */
 	RELOPT_KIND_LAST_DEFAULT = RELOPT_KIND_PARTITIONED,
 	/* some compilers treat enums as signed ints, so we can't use 1 << 31 */
 	RELOPT_KIND_MAX = (1 << 30)
 } relopt_kind;
 
-/* reloption namespaces allowed for heaps -- currently only TOAST */
-#define HEAP_RELOPT_NAMESPACES { "toast", NULL }
-
 /* generic struct to hold shared data */
 typedef struct relopt_gen
 {
diff --git a/src/include/catalog/toasting.h b/src/include/catalog/toasting.h
index 0bc61a8fee9..13e5a8affcb 100644
--- a/src/include/catalog/toasting.h
+++ b/src/include/catalog/toasting.h
@@ -19,10 +19,10 @@
 /*
  * toasting.c prototypes
  */
-extern void NewRelationCreateToastTable(Oid relOid, Datum reloptions);
-extern void NewHeapCreateToastTable(Oid relOid, Datum reloptions,
+extern void NewRelationCreateToastTable(Oid relOid);
+extern void NewHeapCreateToastTable(Oid relOid,
 									LOCKMODE lockmode, Oid OIDOldToast);
-extern void AlterTableCreateToastTable(Oid relOid, Datum reloptions,
+extern void AlterTableCreateToastTable(Oid relOid,
 									   LOCKMODE lockmode);
 extern void BootstrapToastTable(char *relName,
 								Oid toastOid, Oid toastIndexOid);
diff --git a/src/test/modules/injection_points/expected/vacuum.out b/src/test/modules/injection_points/expected/vacuum.out
index 58df59fa927..dcfa729d05e 100644
--- a/src/test/modules/injection_points/expected/vacuum.out
+++ b/src/test/modules/injection_points/expected/vacuum.out
@@ -43,29 +43,29 @@ SELECT injection_points_attach('vacuum-truncate-enabled', 'notice');
 (1 row)
 
 -- Check state of index_cleanup and truncate in VACUUM.
-CREATE TABLE vac_tab_on_toast_off(i int, j text) WITH
+CREATE TABLE vac_tab_on_toast(i int, j text) WITH
   (autovacuum_enabled=false,
-   vacuum_index_cleanup=true, toast.vacuum_index_cleanup=false,
-   vacuum_truncate=true, toast.vacuum_truncate=false);
-CREATE TABLE vac_tab_off_toast_on(i int, j text) WITH
+   vacuum_index_cleanup=true,
+   vacuum_truncate=true);
+CREATE TABLE vac_tab_off_toast(i int, j text) WITH
   (autovacuum_enabled=false,
-   vacuum_index_cleanup=false, toast.vacuum_index_cleanup=true,
-   vacuum_truncate=false, toast.vacuum_truncate=true);
+   vacuum_index_cleanup=false,
+   vacuum_truncate=false);
 -- Multiple relations should use their options in isolation.
-VACUUM vac_tab_on_toast_off, vac_tab_off_toast_on;
+VACUUM vac_tab_on_toast, vac_tab_off_toast;
+NOTICE:  notice triggered for injection point vacuum-index-cleanup-enabled
+NOTICE:  notice triggered for injection point vacuum-truncate-enabled
 NOTICE:  notice triggered for injection point vacuum-index-cleanup-enabled
 NOTICE:  notice triggered for injection point vacuum-truncate-enabled
 NOTICE:  notice triggered for injection point vacuum-index-cleanup-disabled
 NOTICE:  notice triggered for injection point vacuum-truncate-disabled
 NOTICE:  notice triggered for injection point vacuum-index-cleanup-disabled
 NOTICE:  notice triggered for injection point vacuum-truncate-disabled
-NOTICE:  notice triggered for injection point vacuum-index-cleanup-enabled
-NOTICE:  notice triggered for injection point vacuum-truncate-enabled
 -- Check "auto" case of index_cleanup and "truncate" controlled by
 -- its GUC.
 CREATE TABLE vac_tab_auto(i int, j text) WITH
   (autovacuum_enabled=false,
-   vacuum_index_cleanup=auto, toast.vacuum_index_cleanup=auto);
+   vacuum_index_cleanup=auto);
 SET vacuum_truncate = false;
 VACUUM vac_tab_auto;
 NOTICE:  notice triggered for injection point vacuum-index-cleanup-auto
@@ -80,8 +80,8 @@ NOTICE:  notice triggered for injection point vacuum-index-cleanup-auto
 NOTICE:  notice triggered for injection point vacuum-truncate-enabled
 RESET vacuum_truncate;
 DROP TABLE vac_tab_auto;
-DROP TABLE vac_tab_on_toast_off;
-DROP TABLE vac_tab_off_toast_on;
+DROP TABLE vac_tab_on_toast;
+DROP TABLE vac_tab_off_toast;
 -- Cleanup
 SELECT injection_points_detach('vacuum-index-cleanup-auto');
  injection_points_detach 
diff --git a/src/test/modules/injection_points/sql/vacuum.sql b/src/test/modules/injection_points/sql/vacuum.sql
index 23760dd0f38..ee7a2e0566e 100644
--- a/src/test/modules/injection_points/sql/vacuum.sql
+++ b/src/test/modules/injection_points/sql/vacuum.sql
@@ -11,22 +11,22 @@ SELECT injection_points_attach('vacuum-truncate-disabled', 'notice');
 SELECT injection_points_attach('vacuum-truncate-enabled', 'notice');
 
 -- Check state of index_cleanup and truncate in VACUUM.
-CREATE TABLE vac_tab_on_toast_off(i int, j text) WITH
+CREATE TABLE vac_tab_on_toast(i int, j text) WITH
   (autovacuum_enabled=false,
-   vacuum_index_cleanup=true, toast.vacuum_index_cleanup=false,
-   vacuum_truncate=true, toast.vacuum_truncate=false);
-CREATE TABLE vac_tab_off_toast_on(i int, j text) WITH
+   vacuum_index_cleanup=true,
+   vacuum_truncate=true);
+CREATE TABLE vac_tab_off_toast(i int, j text) WITH
   (autovacuum_enabled=false,
-   vacuum_index_cleanup=false, toast.vacuum_index_cleanup=true,
-   vacuum_truncate=false, toast.vacuum_truncate=true);
+   vacuum_index_cleanup=false,
+   vacuum_truncate=false);
 -- Multiple relations should use their options in isolation.
-VACUUM vac_tab_on_toast_off, vac_tab_off_toast_on;
+VACUUM vac_tab_on_toast, vac_tab_off_toast;
 
 -- Check "auto" case of index_cleanup and "truncate" controlled by
 -- its GUC.
 CREATE TABLE vac_tab_auto(i int, j text) WITH
   (autovacuum_enabled=false,
-   vacuum_index_cleanup=auto, toast.vacuum_index_cleanup=auto);
+   vacuum_index_cleanup=auto);
 SET vacuum_truncate = false;
 VACUUM vac_tab_auto;
 SET vacuum_truncate = true;
@@ -34,8 +34,8 @@ VACUUM vac_tab_auto;
 RESET vacuum_truncate;
 
 DROP TABLE vac_tab_auto;
-DROP TABLE vac_tab_on_toast_off;
-DROP TABLE vac_tab_off_toast_on;
+DROP TABLE vac_tab_on_toast;
+DROP TABLE vac_tab_off_toast;
 
 -- Cleanup
 SELECT injection_points_detach('vacuum-index-cleanup-auto');
diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 6dd22be0e8d..435e6beea0f 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -2860,15 +2860,6 @@ select * from my_locks order by 1;
  pg_toast  | ShareUpdateExclusiveLock
 (2 rows)
 
-commit;
-begin; alter table alterlock set (toast.autovacuum_enabled = off);
-select * from my_locks order by 1;
-  relname  |       max_lockmode       
------------+--------------------------
- alterlock | ShareUpdateExclusiveLock
- pg_toast  | ShareUpdateExclusiveLock
-(2 rows)
-
 commit;
 begin; alter table alterlock set (autovacuum_enabled = off);
 select * from my_locks order by 1;
diff --git a/src/test/regress/expected/reloptions.out b/src/test/regress/expected/reloptions.out
index e3a974f2611..eff5fbece60 100644
--- a/src/test/regress/expected/reloptions.out
+++ b/src/test/regress/expected/reloptions.out
@@ -120,7 +120,6 @@ SELECT reloptions FROM pg_class WHERE oid = 'reloptions_test'::regclass;
 DROP TABLE reloptions_test;
 CREATE TEMP TABLE reloptions_test(i INT NOT NULL, j text)
 	WITH (vacuum_truncate=false,
-	toast.vacuum_truncate=false,
 	autovacuum_enabled=false);
 SELECT reloptions FROM pg_class WHERE oid = 'reloptions_test'::regclass;
                     reloptions                    
@@ -142,9 +141,9 @@ SELECT pg_relation_size('reloptions_test') > 0;
 SELECT reloptions FROM pg_class WHERE oid =
 	(SELECT reltoastrelid FROM pg_class
 	WHERE oid = 'reloptions_test'::regclass);
-       reloptions        
--------------------------
- {vacuum_truncate=false}
+ reloptions 
+------------
+ 
 (1 row)
 
 ALTER TABLE reloptions_test RESET (vacuum_truncate);
@@ -165,56 +164,11 @@ SELECT pg_relation_size('reloptions_test') = 0;
  t
 (1 row)
 
--- Test toast.* options
-DROP TABLE reloptions_test;
-CREATE TABLE reloptions_test (s VARCHAR)
-	WITH (toast.autovacuum_vacuum_cost_delay = 23);
-SELECT reltoastrelid as toast_oid
-	FROM pg_class WHERE oid = 'reloptions_test'::regclass \gset
-SELECT reloptions FROM pg_class WHERE oid = :toast_oid;
-            reloptions             
------------------------------------
- {autovacuum_vacuum_cost_delay=23}
-(1 row)
-
-ALTER TABLE reloptions_test SET (toast.autovacuum_vacuum_cost_delay = 24);
-SELECT reloptions FROM pg_class WHERE oid = :toast_oid;
-            reloptions             
------------------------------------
- {autovacuum_vacuum_cost_delay=24}
-(1 row)
-
-ALTER TABLE reloptions_test RESET (toast.autovacuum_vacuum_cost_delay);
-SELECT reloptions FROM pg_class WHERE oid = :toast_oid;
- reloptions 
-------------
- 
-(1 row)
-
--- Fail on non-existent options in toast namespace
-CREATE TABLE reloptions_test2 (i int) WITH (toast.not_existing_option = 42);
-ERROR:  unrecognized parameter "not_existing_option"
--- Mix TOAST & heap
-DROP TABLE reloptions_test;
-CREATE TABLE reloptions_test (s VARCHAR) WITH
-	(toast.autovacuum_vacuum_cost_delay = 23,
-	autovacuum_vacuum_cost_delay = 24, fillfactor = 40);
-SELECT reloptions FROM pg_class WHERE oid = 'reloptions_test'::regclass;
-                   reloptions                    
--------------------------------------------------
- {autovacuum_vacuum_cost_delay=24,fillfactor=40}
-(1 row)
-
-SELECT reloptions FROM pg_class WHERE oid = (
-	SELECT reltoastrelid FROM pg_class WHERE oid = 'reloptions_test'::regclass);
-            reloptions             
------------------------------------
- {autovacuum_vacuum_cost_delay=23}
-(1 row)
-
 --
 -- CREATE INDEX, ALTER INDEX for btrees
 --
+DROP TABLE reloptions_test;
+CREATE TABLE reloptions_test (s VARCHAR);
 CREATE INDEX reloptions_test_idx ON reloptions_test (s) WITH (fillfactor=30);
 SELECT reloptions FROM pg_class WHERE oid = 'reloptions_test_idx'::regclass;
    reloptions    
diff --git a/src/test/regress/expected/vacuum.out b/src/test/regress/expected/vacuum.out
index d4696bc3325..d551ef57d50 100644
--- a/src/test/regress/expected/vacuum.out
+++ b/src/test/regress/expected/vacuum.out
@@ -209,14 +209,6 @@ VACUUM no_index_cleanup;
 INSERT INTO no_index_cleanup(i, t) VALUES (generate_series(31,60),
     repeat('1234567890',269));
 DELETE FROM no_index_cleanup WHERE i < 45;
--- Only toast index is cleaned up.
-ALTER TABLE no_index_cleanup SET (vacuum_index_cleanup = off,
-    toast.vacuum_index_cleanup = yes);
-VACUUM no_index_cleanup;
--- Only parent is cleaned up.
-ALTER TABLE no_index_cleanup SET (vacuum_index_cleanup = true,
-    toast.vacuum_index_cleanup = false);
-VACUUM no_index_cleanup;
 -- Test some extra relations.
 VACUUM (INDEX_CLEANUP FALSE) vaccluster;
 VACUUM (INDEX_CLEANUP AUTO) vactst; -- index cleanup option is ignored if no indexes
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index f5f13bbd3e7..410465dc022 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -1784,10 +1784,6 @@ begin; alter table alterlock reset (fillfactor);
 select * from my_locks order by 1;
 commit;
 
-begin; alter table alterlock set (toast.autovacuum_enabled = off);
-select * from my_locks order by 1;
-commit;
-
 begin; alter table alterlock set (autovacuum_enabled = off);
 select * from my_locks order by 1;
 commit;
diff --git a/src/test/regress/sql/reloptions.sql b/src/test/regress/sql/reloptions.sql
index 680c8bf8614..0809a2ae0e4 100644
--- a/src/test/regress/sql/reloptions.sql
+++ b/src/test/regress/sql/reloptions.sql
@@ -75,7 +75,6 @@ DROP TABLE reloptions_test;
 
 CREATE TEMP TABLE reloptions_test(i INT NOT NULL, j text)
 	WITH (vacuum_truncate=false,
-	toast.vacuum_truncate=false,
 	autovacuum_enabled=false);
 SELECT reloptions FROM pg_class WHERE oid = 'reloptions_test'::regclass;
 INSERT INTO reloptions_test VALUES (1, NULL), (NULL, NULL);
@@ -94,39 +93,12 @@ INSERT INTO reloptions_test VALUES (1, NULL), (NULL, NULL);
 VACUUM (FREEZE, DISABLE_PAGE_SKIPPING) reloptions_test;
 SELECT pg_relation_size('reloptions_test') = 0;
 
--- Test toast.* options
-DROP TABLE reloptions_test;
-
-CREATE TABLE reloptions_test (s VARCHAR)
-	WITH (toast.autovacuum_vacuum_cost_delay = 23);
-SELECT reltoastrelid as toast_oid
-	FROM pg_class WHERE oid = 'reloptions_test'::regclass \gset
-SELECT reloptions FROM pg_class WHERE oid = :toast_oid;
-
-ALTER TABLE reloptions_test SET (toast.autovacuum_vacuum_cost_delay = 24);
-SELECT reloptions FROM pg_class WHERE oid = :toast_oid;
-
-ALTER TABLE reloptions_test RESET (toast.autovacuum_vacuum_cost_delay);
-SELECT reloptions FROM pg_class WHERE oid = :toast_oid;
-
--- Fail on non-existent options in toast namespace
-CREATE TABLE reloptions_test2 (i int) WITH (toast.not_existing_option = 42);
-
--- Mix TOAST & heap
-DROP TABLE reloptions_test;
-
-CREATE TABLE reloptions_test (s VARCHAR) WITH
-	(toast.autovacuum_vacuum_cost_delay = 23,
-	autovacuum_vacuum_cost_delay = 24, fillfactor = 40);
-
-SELECT reloptions FROM pg_class WHERE oid = 'reloptions_test'::regclass;
-SELECT reloptions FROM pg_class WHERE oid = (
-	SELECT reltoastrelid FROM pg_class WHERE oid = 'reloptions_test'::regclass);
-
 --
 -- CREATE INDEX, ALTER INDEX for btrees
 --
+DROP TABLE reloptions_test;
 
+CREATE TABLE reloptions_test (s VARCHAR);
 CREATE INDEX reloptions_test_idx ON reloptions_test (s) WITH (fillfactor=30);
 SELECT reloptions FROM pg_class WHERE oid = 'reloptions_test_idx'::regclass;
 
diff --git a/src/test/regress/sql/vacuum.sql b/src/test/regress/sql/vacuum.sql
index 247b8e23b23..37a84fd9145 100644
--- a/src/test/regress/sql/vacuum.sql
+++ b/src/test/regress/sql/vacuum.sql
@@ -175,14 +175,6 @@ VACUUM no_index_cleanup;
 INSERT INTO no_index_cleanup(i, t) VALUES (generate_series(31,60),
     repeat('1234567890',269));
 DELETE FROM no_index_cleanup WHERE i < 45;
--- Only toast index is cleaned up.
-ALTER TABLE no_index_cleanup SET (vacuum_index_cleanup = off,
-    toast.vacuum_index_cleanup = yes);
-VACUUM no_index_cleanup;
--- Only parent is cleaned up.
-ALTER TABLE no_index_cleanup SET (vacuum_index_cleanup = true,
-    toast.vacuum_index_cleanup = false);
-VACUUM no_index_cleanup;
 -- Test some extra relations.
 VACUUM (INDEX_CLEANUP FALSE) vaccluster;
 VACUUM (INDEX_CLEANUP AUTO) vactst; -- index cleanup option is ignored if no indexes
-- 
2.50.1 (Apple Git-155)


--g1KZ71ry6DNksXN0--






^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* [PATCH v2 1/2] Do not lock tables in get_tables_to_repack().
@ 2026-06-16 06:49 ChangAo Chen <cca5507@qq.com>
  0 siblings, 0 replies; 332+ messages in thread

From: ChangAo Chen @ 2026-06-16 06:49 UTC (permalink / raw)

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index faa07d1a118..2879c8af574 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2169,22 +2169,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2192,7 +2179,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2201,10 +2187,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2228,45 +2211,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2279,7 +2237,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2357,15 +2315,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.47.3


--op6mnexl7cn72cto
Content-Type: text/x-diff; charset=utf-8
Content-Disposition: attachment; filename=v2-0002-fixups.patch



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* Do not lock tables in get_tables_to_repack
@ 2026-06-16 07:34 =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-06-27 19:56 ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
  2026-07-07 16:53 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  0 siblings, 2 replies; 332+ messages in thread

From: =?utf-8?B?Y2NhNTUwNw==?= @ 2026-06-16 07:34 UTC (permalink / raw)
  To: =?utf-8?B?cGdzcWwtaGFja2Vycw==?= <pgsql-hackers@lists.postgresql.org>

Hi hackers,

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

Thoughts?

--
Regards,
ChangAo Chen


Attachments:

  [application/octet-stream] v1-0001-Do-not-lock-tables-in-get_tables_to_repack.patch (5.4K, ../../tencent_9F290B256A3F52B66542F1140E32ECC64309@qq.com/2-v1-0001-Do-not-lock-tables-in-get_tables_to_repack.patch)
  download | inline diff:
From fa5c3073f2f41cf3c8ab7c9663b681e6140a4824 Mon Sep 17 00:00:00 2001
From: ChangAo Chen <cca5507@qq.com>
Date: Tue, 16 Jun 2026 14:49:49 +0800
Subject: [PATCH v1] Do not lock tables in get_tables_to_repack().

When doing a whole database repack, we build a list of repackable
tables and take a lock on them to prevent concurrent drops. But
concurrent drops can always happen after we build the list because
we process each table in a separate transaction. The
ConditionalLockRelationOid() also makes the default behavior like
SKIP_LOCKED, which is unexpected.

To remove the locks, we need to make repack_is_permitted_for_relation()
handles concurrent drops correctly: it should not report an error
when failing to search the syscache in pg_class_aclcheck(). Use
pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
check the return value of get_rel_name().

While at it, replace relation_close() with table_close() to match
the table_open().
---
 src/backend/commands/repack.c | 67 ++++++++++-------------------------
 1 file changed, 19 insertions(+), 48 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index ec100e3eef5..6f25effeed2 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -2159,22 +2159,9 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			index = (Form_pg_index) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the index's table, to ensure it
-			 * doesn't go away while we collect the list.  If we cannot, just
-			 * disregard it.  Be sure to release this if we ultimately decide
-			 * not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(index->indrelid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists; skip if not */
 			classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
 			if (!HeapTupleIsValid(classtup))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 			classForm = (Form_pg_class) GETSTRUCT(classtup);
 
 			/* Skip temp relations belonging to other sessions */
@@ -2182,7 +2169,6 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 				!isTempOrTempToastNamespace(classForm->relnamespace))
 			{
 				ReleaseSysCache(classtup);
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
 			}
 
@@ -2191,10 +2177,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(index->indrelid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2218,45 +2201,20 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			class = (Form_pg_class) GETSTRUCT(tuple);
 
-			/*
-			 * Try to obtain a light lock on the table, to ensure it doesn't
-			 * go away while we collect the list.  If we cannot, just
-			 * disregard the table.  Be sure to release this if we ultimately
-			 * decide not to process the table!
-			 */
-			if (!ConditionalLockRelationOid(class->oid, AccessShareLock))
-				continue;
-
-			/* Verify that the table still exists */
-			if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(class->oid)))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
-				continue;
-			}
-
 			/* Can only process plain tables and matviews */
 			if (class->relkind != RELKIND_RELATION &&
 				class->relkind != RELKIND_MATVIEW)
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Skip temp relations belonging to other sessions */
 			if (class->relpersistence == RELPERSISTENCE_TEMP &&
 				!isTempOrTempToastNamespace(class->relnamespace))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
 												  GetUserId()))
-			{
-				UnlockRelationOid(class->oid, AccessShareLock);
 				continue;
-			}
 
 			/* Use a permanent memory context for the result list */
 			oldcxt = MemoryContextSwitchTo(permcxt);
@@ -2269,7 +2227,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 	}
 
 	table_endscan(scan);
-	relation_close(catalog, AccessShareLock);
+	table_close(catalog, AccessShareLock);
 
 	return rtcs;
 }
@@ -2347,15 +2305,28 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 static bool
 repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 {
+	bool		is_missing = false;
+
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	if (pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK)
+	if (pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing) == ACLCHECK_OK)
 		return true;
 
-	ereport(WARNING,
-			errmsg("permission denied to execute %s on \"%s\", skipping it",
-				   RepackCommandAsString(cmd),
-				   get_rel_name(relid)));
+	/* Report a warning if the relation still exists. */
+	if (!is_missing)
+	{
+		char	   *relname;
+
+		relname = get_rel_name(relid);
+		if (relname != NULL)
+		{
+			ereport(WARNING,
+					errmsg("permission denied to execute %s on \"%s\", skipping it",
+						   RepackCommandAsString(cmd), relname));
+
+			pfree(relname);
+		}
+	}
 
 	return false;
 }
-- 
2.34.1



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* Re: Do not lock tables in get_tables_to_repack
  2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
@ 2026-06-27 19:56 ` Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
  1 sibling, 0 replies; 332+ messages in thread

From: Bharath Rupireddy @ 2026-06-27 19:56 UTC (permalink / raw)
  To: cca5507 <cca5507@qq.com>; +Cc: pgsql-hackers <pgsql-hackers@lists.postgresql.org>; Antonin Houska <ah@cybertec.at>; Alvaro Herrera <alvherre@alvh.no-ip.org>

Hi,

On Tue, Jun 16, 2026 at 12:35 AM cca5507 <cca5507@qq.com> wrote:
>
> Hi hackers,
>
> When doing a whole database repack, we build a list of repackable
> tables and take a lock on them to prevent concurrent drops. But
> concurrent drops can always happen after we build the list because
> we process each table in a separate transaction. The
> ConditionalLockRelationOid() also makes the default behavior like
> SKIP_LOCKED, which is unexpected.
>
> To remove the locks, we need to make repack_is_permitted_for_relation()
> handles concurrent drops correctly: it should not report an error
> when failing to search the syscache in pg_class_aclcheck(). Use
> pg_class_aclcheck_ext() instead to detect a concurrent drop. Also
> check the return value of get_rel_name().
>
> Thoughts?

I don't have a strong opinion on fixing this for REPACK. For vacuum,
we wanted to get consistent behavior across all modes of invoking it
[1]. Whether to handle concurrent drops for REPACK depends on how long
it spends scanning pg_index/pg_class in get_tables_to_repack. Also,
vacuum is more commonly run database-wide (against all tables), and
without field experience showing this is a real problem for REPACK,
I'm not sure the fix is needed. That said, others may have a different
take - adding the REPACK authors here for their input.

[1] https://www.postgresql.org/message-id/CALj2ACUbhDFJWSwiyoUxXED2S2fr9Xis%3D08Rnjq53UzBE4FvzA%40mail.g...

--
Bharath Rupireddy
Amazon Web Services: https://aws.amazon.com





^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* Re: Do not lock tables in get_tables_to_repack
  2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
@ 2026-07-07 16:53 ` Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-08 02:36   ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  1 sibling, 1 reply; 332+ messages in thread

From: Álvaro Herrera @ 2026-07-07 16:53 UTC (permalink / raw)
  To: cca5507 <cca5507@qq.com>; +Cc: pgsql-hackers <pgsql-hackers@lists.postgresql.org>

On 2026-Jun-16, cca5507 wrote:

> Hi hackers,
> 
> When doing a whole database repack, we build a list of repackable
> tables and take a lock on them to prevent concurrent drops. But
> concurrent drops can always happen after we build the list because
> we process each table in a separate transaction.

Not only that.  We have actually three ways to obtain the list of tables
to repack, and only one of these obtains the locks.  So this code is
internally inconsistent.  I agree that we should do something like your
patch.  I wanted to be a little more defensive though; how about the
attached?

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/


^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* Re: Do not lock tables in get_tables_to_repack
  2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-07 16:53 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
@ 2026-07-08 02:36   ` =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-10 14:22     ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  0 siblings, 1 reply; 332+ messages in thread

From: =?utf-8?B?Y2NhNTUwNw==?= @ 2026-07-08 02:36 UTC (permalink / raw)
  To: =?utf-8?B?w4FsdmFybyBIZXJyZXJh?= <alvherre@kurilemu.de>; +Cc: =?utf-8?B?cGdzcWwtaGFja2Vycw==?= <pgsql-hackers@lists.postgresql.org>

> > Hi hackers,
> > 
> > When doing a whole database repack, we build a list of repackable
> > tables and take a lock on them to prevent concurrent drops. But
> > concurrent drops can always happen after we build the list because
> > we process each table in a separate transaction.
> 
> Not only that.  We have actually three ways to obtain the list of tables
> to repack, and only one of these obtains the locks.  So this code is
> internally inconsistent.  I agree that we should do something like your
> patch.  I wanted to be a little more defensive though; how about the
> attached?

-                       classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
+                       classtup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(index->indrelid));

Do we really need to copy it? We hold a refcount on it so it won't be freed
until we release it. Otherwise LGTM.

--
Regards,
ChangAo Chen


^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* Re: Do not lock tables in get_tables_to_repack
  2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-07 16:53 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-08 02:36   ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
@ 2026-07-10 14:22     ` Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-10 16:03       ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
  0 siblings, 1 reply; 332+ messages in thread

From: Álvaro Herrera @ 2026-07-10 14:22 UTC (permalink / raw)
  To: cca5507 <cca5507@qq.com>; +Cc: pgsql-hackers <pgsql-hackers@lists.postgresql.org>

On 2026-Jul-08, cca5507 wrote:

> -                       classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
> +                       classtup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(index->indrelid));
> 
> Do we really need to copy it? We hold a refcount on it so it won't be freed
> until we release it. Otherwise LGTM.

Yeah, I guess it doesn't matter.  I have removed the copy and updated
some comments.  I also realized that there are some places where we
weren't dealing correctly with the possibility that the relation goes
away, or is replaced with something different, so I added that too.

While looking at it I also realized that get_tables_to_repack_partitioned
is likewise not careful enough about it: we do IndexGetRelation(, false)
which fails hard if the pg_index tuple cannot be found, which is the
wrong thing to do.

At the same time, it's annoying that half of the code that clearly
belongs in that routine is actually in ExecRepack().  I moved that to
where it rightfully belongs.  (The only somewhat annoying thing is that
we have to NULL-out the Relation pointer after returning; but that's not
*too* bad IMO.)

Any opinions on this?

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/
"No me acuerdo, pero no es cierto.  No es cierto, y si fuera cierto,
 no me acuerdo."                 (Augusto Pinochet a una corte de justicia)


^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* Re: Do not lock tables in get_tables_to_repack
  2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-07 16:53 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-08 02:36   ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-10 14:22     ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
@ 2026-07-10 16:03       ` Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
  2026-07-10 17:34         ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
  0 siblings, 1 reply; 332+ messages in thread

From: Bharath Rupireddy @ 2026-07-10 16:03 UTC (permalink / raw)
  To: Álvaro Herrera <alvherre@kurilemu.de>; +Cc: cca5507 <cca5507@qq.com>; pgsql-hackers <pgsql-hackers@lists.postgresql.org>

Hi,

On Fri, Jul 10, 2026 at 7:22 AM Álvaro Herrera <alvherre@kurilemu.de> wrote:
>
> On 2026-Jul-08, cca5507 wrote:
>
> > -                       classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(index->indrelid));
> > +                       classtup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(index->indrelid));
> >
> > Do we really need to copy it? We hold a refcount on it so it won't be freed
> > until we release it. Otherwise LGTM.

Thanks for committing this.

Here is my overall take. Even before this commit, a database-wide
REPACK does not error on a concurrently dropped table.
get_tables_to_repack takes a brief lock on each table before the ACL
check, which blocks a concurrent drop while the list is being built.
Later each table is re-opened under its lock and skipped if it is
already gone. So the brief lock is not needed for correctness. What it
does is let an unprivileged user lock relations it may not even be
allowed to repack, including system catalogs, before we have checked
its privileges. I am fine with removing the lock as the commit did.

I would also like to tighten repack_is_permitted_for_relation so a
caller that holds a lock still errors out on a missing relation
instead of skipping it silently
(https://www.postgresql.org/message-id/akPhEffRipH4isWF%40nathan).
Attached as a follow-up patch. Please have a look.

> Yeah, I guess it doesn't matter.  I have removed the copy and updated
> some comments.  I also realized that there are some places where we
> weren't dealing correctly with the possibility that the relation goes
> away, or is replaced with something different, so I added that too.

I agree that the SearchSysCacheCopy1 in v2-0002 adds no benefit. Since
no lock is held on the relation, there is no point in copying the
syscache tuple.

> While looking at it I also realized that get_tables_to_repack_partitioned
> is likewise not careful enough about it: we do IndexGetRelation(, false)
> which fails hard if the pg_index tuple cannot be found, which is the
> wrong thing to do.
>
> At the same time, it's annoying that half of the code that clearly
> belongs in that routine is actually in ExecRepack().  I moved that to
> where it rightfully belongs.  (The only somewhat annoying thing is that
> we have to NULL-out the Relation pointer after returning; but that's not
> *too* bad IMO.)
>
> Any opinions on this?

I will take a closer look at this in a bit.

--
Bharath Rupireddy
Amazon Web Services: https://aws.amazon.com


Attachments:

  [application/octet-stream] v1-0001-Tighten-ACL-check-in-repack_is_permitted_for_rela.patch (5.1K, ../../CALj2ACX3pyuRS8++6L20cJUMRTf_qbbVp69J1btJ3y6=77e5gw@mail.gmail.com/2-v1-0001-Tighten-ACL-check-in-repack_is_permitted_for_rela.patch)
  download | inline diff:
From 6729b2f14ed623a8b38f5a530b8c85c96bfd5b40 Mon Sep 17 00:00:00 2001
From: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Date: Fri, 10 Jul 2026 15:42:47 +0000
Subject: [PATCH v1] Tighten ACL check in repack_is_permitted_for_relation()

Commit c71d43025d7 made repack_is_permitted_for_relation() use
_ext() and skip a concurrently dropped relation silently. That is
fine for the callers that hold no lock on the relation, but it is
applied unconditionally, including where we may already hold a
lock on the relation whose ACL is checked. In that case missing a
relation is not fine, so this made the code more brittle: a
missing relation there would indicate a bug and should error out
rather than be skipped silently.

Add a missing_ok flag so the silent skip is done only where no
lock is held. Callers that hold a lock pass false and still error
out on a missing relation.
---
 src/backend/commands/repack.c | 38 ++++++++++++++++++++++++-----------
 1 file changed, 26 insertions(+), 12 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index 02883fe34a4..b09be65da3b 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -172,8 +172,8 @@ static List *get_tables_to_repack(RepackCommand cmd, bool usingindex,
 static List *get_tables_to_repack_partitioned(RepackCommand cmd,
 											  Oid relid, bool rel_is_index,
 											  MemoryContext permcxt);
-static bool repack_is_permitted_for_relation(RepackCommand cmd,
-											 Oid relid, Oid userid);
+static bool repack_is_permitted_for_relation(RepackCommand cmd, Oid relid,
+											 Oid userid, bool missing_ok);
 
 static void apply_concurrent_changes(BufFile *file, ChangeContext *chgcxt);
 static void apply_concurrent_insert(Relation rel, TupleTableSlot *slot,
@@ -724,7 +724,7 @@ cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid,
 	Assert(CheckRelationLockedByMe(OldHeap, lmode, false));
 
 	/* Check that the user still has privileges for the relation */
-	if (!repack_is_permitted_for_relation(cmd, tableOid, userid))
+	if (!repack_is_permitted_for_relation(cmd, tableOid, userid, false))
 	{
 		relation_close(OldHeap, lmode);
 		return false;
@@ -2198,7 +2198,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, index->indrelid,
-												  GetUserId()))
+												  GetUserId(), true))
 				continue;
 
 			/* Use a permanent memory context for the result list */
@@ -2235,7 +2235,7 @@ get_tables_to_repack(RepackCommand cmd, bool usingindex, MemoryContext permcxt)
 
 			/* noisily skip rels which the user can't process */
 			if (!repack_is_permitted_for_relation(cmd, class->oid,
-												  GetUserId()))
+												  GetUserId(), true))
 				continue;
 
 			/* Use a permanent memory context for the result list */
@@ -2304,7 +2304,7 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 		 * leaf partition despite having them on the partitioned table.  Skip
 		 * if so.
 		 */
-		if (!repack_is_permitted_for_relation(cmd, table_oid, GetUserId()))
+		if (!repack_is_permitted_for_relation(cmd, table_oid, GetUserId(), true))
 			continue;
 
 		/* Use a permanent memory context for the result list */
@@ -2321,16 +2321,21 @@ get_tables_to_repack_partitioned(RepackCommand cmd, Oid relid,
 
 
 /*
- * Return whether userid has privileges to execute REPACK on relid.
+ * Check whether the passed-in user has privileges to execute REPACK on the
+ * relation.
  *
- * Caller may not have a lock on the relation, so it could have been
- * dropped concurrently.  In that case, silently return false.
+ * missing_ok should be passed only by callers that hold no lock on the
+ * relation, where a concurrent drop is possible and fine to skip. A caller
+ * that holds a lock must not pass it: there a missing relation would indicate
+ * a bug and should error out rather than be silently skipped.
  *
  * If the relation does exist but the user doesn't have the required
- * privs, emit a WARNING and return false.  Otherwise, return true.
+ * privileges, emit a WARNING and return false to let the caller
+ * decide what to do with this relation.
  */
 static bool
-repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
+repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid,
+								 bool missing_ok)
 {
 	bool		is_missing = false;
 	AclResult	result;
@@ -2338,9 +2343,18 @@ repack_is_permitted_for_relation(RepackCommand cmd, Oid relid, Oid userid)
 
 	Assert(cmd == REPACK_COMMAND_CLUSTER || cmd == REPACK_COMMAND_REPACK);
 
-	result = pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN, &is_missing);
+	result = pg_class_aclcheck_ext(relid, userid, ACL_MAINTAIN,
+								   missing_ok ? &is_missing : NULL);
+
+	/*
+	 * If the relation was concurrently dropped, nothing to do. Note that this
+	 * is only reachable when the caller specified missing_ok.
+	 */
 	if (is_missing)
+	{
+		Assert(missing_ok);
 		return false;
+	}
 
 	if (result == ACLCHECK_OK)
 		return true;
-- 
2.47.3



^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* Re: Do not lock tables in get_tables_to_repack
  2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-07 16:53 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-08 02:36   ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-10 14:22     ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-10 16:03       ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
@ 2026-07-10 17:34         ` Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
  2026-07-11 14:50           ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  0 siblings, 1 reply; 332+ messages in thread

From: Bharath Rupireddy @ 2026-07-10 17:34 UTC (permalink / raw)
  To: Álvaro Herrera <alvherre@kurilemu.de>; +Cc: cca5507 <cca5507@qq.com>; pgsql-hackers <pgsql-hackers@lists.postgresql.org>

Hi,

On Fri, Jul 10, 2026 at 9:03 AM Bharath Rupireddy
<bharath.rupireddyforpostgres@gmail.com> wrote:
>
> > While looking at it I also realized that get_tables_to_repack_partitioned
> > is likewise not careful enough about it: we do IndexGetRelation(, false)
> > which fails hard if the pg_index tuple cannot be found, which is the
> > wrong thing to do.

Agreed. For a single-level partitioned table, dropping a leaf blocks
on the parent's AccessExclusiveLock, which REPACK holds, so the leaf
can't go away mid-build. But for a multi-level table, REPACK holds a
lock only on the top parent, so a lower-level leaf whose immediate
parent is an intermediate table isn't protected and can be dropped
concurrently. So IndexGetRelation(, false) failing hard there is
indeed the wrong thing.

> > At the same time, it's annoying that half of the code that clearly
> > belongs in that routine is actually in ExecRepack().  I moved that to
> > where it rightfully belongs.

+1, that's a good cleanup. That code clearly belongs in
get_tables_to_repack_partitioned().

>> (The only somewhat annoying thing is that
> > we have to NULL-out the Relation pointer after returning; but that's not
> > *too* bad IMO.)

That's fine. We already NULL out rel after
get_tables_to_repack_partitioned() today, so the patch isn't adding
anything new there. Relying on a non-NULL return from
process_single_relation() to mean partitioned table is a little
indirect on first read, but the comments explains it well, and I
wouldn't complicate the code to avoid it.

> > Any opinions on this?
>
> I will take a closer look at this in a bit.

Patch looks good to me. One nit:

+ table_oid = IndexGetRelation(child_oid, true);
+ if (!OidIsValid(table_oid))
+ continue;

How about a short comment on why this is needed even with a lock on
the parent, since that lock doesn't cover lower-level leaves in a
multi-level partition tree?

--
Bharath Rupireddy
Amazon Web Services: https://aws.amazon.com





^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* Re: Do not lock tables in get_tables_to_repack
  2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-07 16:53 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-08 02:36   ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-10 14:22     ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-10 16:03       ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
  2026-07-10 17:34         ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
@ 2026-07-11 14:50           ` =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-20 10:19             ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  0 siblings, 1 reply; 332+ messages in thread

From: =?utf-8?B?Y2NhNTUwNw==?= @ 2026-07-11 14:50 UTC (permalink / raw)
  To: =?utf-8?B?QmhhcmF0aCBSdXBpcmVkZHk=?= <bharath.rupireddyforpostgres@gmail.com>; =?utf-8?B?w4FsdmFybyBIZXJyZXJh?= <alvherre@kurilemu.de>; +Cc: =?utf-8?B?cGdzcWwtaGFja2Vycw==?= <pgsql-hackers@lists.postgresql.org>

> > > Any opinions on this?
> >
> > I will take a closer look at this in a bit.
> 
> Patch looks good to me. One nit:
> 
> + table_oid = IndexGetRelation(child_oid, true);
> + if (!OidIsValid(table_oid))
> + continue;
> 
> How about a short comment on why this is needed even with a lock on
> the parent, since that lock doesn't cover lower-level leaves in a
> multi-level partition tree?

I think it's worth a comment, too. Patch LGTM.

--
Regards,
ChangAo Chen


^ permalink  raw  reply  [nested|flat] 332+ messages in thread

* Re: Do not lock tables in get_tables_to_repack
  2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-07 16:53 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-08 02:36   ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
  2026-07-10 14:22     ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
  2026-07-10 16:03       ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
  2026-07-10 17:34         ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
  2026-07-11 14:50           ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
@ 2026-07-20 10:19             ` Álvaro Herrera <alvherre@kurilemu.de>
  0 siblings, 0 replies; 332+ messages in thread

From: Álvaro Herrera @ 2026-07-20 10:19 UTC (permalink / raw)
  To: cca5507 <cca5507@qq.com>; +Cc: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>; pgsql-hackers <pgsql-hackers@lists.postgresql.org>

On 2026-Jul-11, cca5507 wrote:

> Bharath Rupireddy wrote:

> > + table_oid = IndexGetRelation(child_oid, true);
> > + if (!OidIsValid(table_oid))
> > + continue;
> > 
> > How about a short comment on why this is needed even with a lock on
> > the parent, since that lock doesn't cover lower-level leaves in a
> > multi-level partition tree?
> 
> I think it's worth a comment, too. Patch LGTM.

Thanks, added that and pushed.

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/
"Puedes vivir sólo una vez, pero si lo haces bien, una vez es suficiente"






^ permalink  raw  reply  [nested|flat] 332+ messages in thread


end of thread, other threads:[~2026-07-20 10:19 UTC | newest]

Thread overview: 332+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2026-04-07 20:30 [PATCH v4 1/1] remove toast reloptions Nathan Bossart <nathan@postgresql.org>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 06:49 [PATCH v2 1/2] Do not lock tables in get_tables_to_repack(). ChangAo Chen <cca5507@qq.com>
2026-06-16 07:34 Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
2026-06-27 19:56 ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
2026-07-07 16:53 ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
2026-07-08 02:36   ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
2026-07-10 14:22     ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>
2026-07-10 16:03       ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
2026-07-10 17:34         ` Re: Do not lock tables in get_tables_to_repack Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
2026-07-11 14:50           ` Re: Do not lock tables in get_tables_to_repack =?utf-8?B?Y2NhNTUwNw==?= <cca5507@qq.com>
2026-07-20 10:19             ` Re: Do not lock tables in get_tables_to_repack Álvaro Herrera <alvherre@kurilemu.de>

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