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help / color / mirror / Atom feedFrom: Bharath Rupireddy <[email protected]>
To: Masahiko Sawada <[email protected]>
Cc: Srinath Reddy Sadipiralla <[email protected]>
Cc: SATYANARAYANA NARLAPURAM <[email protected]>
Cc: Hayato Kuroda (Fujitsu) <[email protected]>
Cc: John H <[email protected]>
Cc: PostgreSQL-development <[email protected]>
Subject: Re: Introduce XID age based replication slot invalidation
Date: Fri, 3 Apr 2026 12:04:48 -0700
Message-ID: <CALj2ACXR=5SoApm6duEOc6pi=-KaBqSxuSP6XNQot2LywrqtAA@mail.gmail.com> (raw)
In-Reply-To: <CALj2ACV724Yr2=5Jun4XGQyGhvCiXo+7GXJUnybqf9SYqQA6gw@mail.gmail.com>
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<CALj2ACV724Yr2=5Jun4XGQyGhvCiXo+7GXJUnybqf9SYqQA6gw@mail.gmail.com>
Hi,
On Wed, Apr 1, 2026 at 2:21 PM Bharath Rupireddy
<[email protected]> wrote:
>
> On Wed, Apr 1, 2026 at 12:39 PM Masahiko Sawada <[email protected]> wrote:
> >
> > I've reviewed the v7 patch and have some review comments:
>
> Thank you for reviewing the patch.
>
> I took the above changes into v8 and fixed a typo in using xidLimit
> instead of slotXidLimit.
>
> Please find the attached v8 patches for further review. Thank you!
Thank you, Sawada-san, for reviewing and providing some offlist comments.
1/ Included a note in the docs to say that logical replication slots
are also affected by XID age GUC (similar to
idle_replication_slot_timeout).
2/ Added the code to disable the XID age invalidation in
pg_createsubscriber similar to timeout invalidation. Commit 72e6c08fea
ensured that none of the logical replication slots get invalidated
during the upgrade. (I believe the work that pg_upgrade and
pg_createsubscriber do is more important, and the slots created and
used by them or slots in use during those processes must not interfere
with the upgrade or creating a logical replica from a standby.)
3/ Changed the max value of XID age GUC to be equal to that of vacuum
failsafe age. In my opinion, the best use of max_slot_xid_age would be
to set it equal to or a little less than vacuum_failsafe_age. Also
added a note in the docs about this.
4/ Changed variable names for consistency.
5/ Added code to MaybeInvalidateXIDAgedSlots() to skip the slot
invalidation attempt (unnecessary work) when slots are not the reason
for holding back the OldestXmin. Added an equality check to see if
OldestXmin is either OldestSlotXmin or OldestSlotCatalogXmin (all
these OldestXXXXmins are computed from the same ComputeXidHorizons()
call). This should allow us to skip the slot invalidation attempt when
a backend is holding the xmin back (a long-running transaction, for
example).
Please find the attached v9 patches for further review. Thank you!
--
Bharath Rupireddy
Amazon Web Services: https://aws.amazon.com
Attachments:
[application/octet-stream] v9-0001-Add-XID-age-based-replication-slot-invalidation.patch (33.6K, 2-v9-0001-Add-XID-age-based-replication-slot-invalidation.patch)
download | inline diff:
From c68a15527999b1f52ed648873b03878a6f1aed32 Mon Sep 17 00:00:00 2001
From: Bharath Rupireddy <[email protected]>
Date: Fri, 3 Apr 2026 18:27:15 +0000
Subject: [PATCH v9 1/2] Add XID age based replication slot invalidation
Introduce max_slot_xid_age, a GUC that invalidates replication
slots whose xmin or catalog_xmin exceeds the specified age.
Disabled by default.
Idle or forgotten replication slots can hold back vacuum, leading
to bloat and eventually XID wraparound. In the worst case this
requires dropping the slot and single-user mode vacuuming. This
setting avoids that by proactively invalidating slots that have
fallen too far behind.
Invalidation checks are performed once per relation during vacuum
(both vacuum command and autovacuum), and also by the checkpointer
during checkpoints and restartpoints.
---
doc/src/sgml/config.sgml | 54 ++++++
doc/src/sgml/logical-replication.sgml | 4 +-
doc/src/sgml/system-views.sgml | 8 +
src/backend/access/heap/vacuumlazy.c | 15 ++
src/backend/access/transam/xlog.c | 34 +++-
src/backend/commands/vacuum.c | 5 +-
src/backend/replication/slot.c | 136 +++++++++++++-
src/backend/storage/ipc/procarray.c | 61 ++++--
src/backend/storage/ipc/standby.c | 3 +-
src/backend/utils/misc/guc_parameters.dat | 8 +
src/backend/utils/misc/postgresql.conf.sample | 2 +
src/bin/pg_basebackup/pg_createsubscriber.c | 2 +-
src/include/commands/vacuum.h | 7 +
src/include/replication/slot.h | 11 +-
src/include/storage/procarray.h | 3 +
src/test/recovery/t/019_replslot_limit.pl | 175 ++++++++++++++++++
16 files changed, 500 insertions(+), 28 deletions(-)
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index fdb77df0fdb..d51a1060bee 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -4764,6 +4764,60 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows
</listitem>
</varlistentry>
+ <varlistentry id="guc-max-slot-xid-age" xreflabel="max_slot_xid_age">
+ <term><varname>max_slot_xid_age</varname> (<type>integer</type>)
+ <indexterm>
+ <primary><varname>max_slot_xid_age</varname> configuration parameter</primary>
+ </indexterm>
+ </term>
+ <listitem>
+ <para>
+ Invalidate replication slots whose <structfield>xmin</structfield> age
+ or <structfield>catalog_xmin</structfield> age in the
+ <link linkend="view-pg-replication-slots">pg_replication_slots</link>
+ view has exceeded the age specified by this setting. Slot invalidation
+ due to this limit occurs during vacuum (both <command>VACUUM</command>
+ command and autovacuum) and during checkpoint.
+ A value of zero (the default) disables this feature. Users can set
+ this value anywhere from zero to two billion transactions. This parameter
+ can only be set in the <filename>postgresql.conf</filename> file or on
+ the server command line.
+ </para>
+
+ <para>
+ The current age of a slot's <literal>xmin</literal> and
+ <literal>catalog_xmin</literal> can be monitored by applying the
+ <function>age</function> function to the corresponding columns in the
+ <link linkend="view-pg-replication-slots">pg_replication_slots</link>
+ view.
+ </para>
+
+ <para>
+ Idle or forgotten replication slots can hold back vacuum, leading to
+ bloat and eventually transaction ID wraparound. This setting avoids
+ that by invalidating slots that have fallen too far behind.
+ See <xref linkend="routine-vacuuming"/> for more details.
+ </para>
+
+ <para>
+ It is recommended to set <varname>max_slot_xid_age</varname>
+ to a value equal to or slightly less than
+ <xref linkend="guc-vacuum-failsafe-age"/>, so that the slot holding the
+ vacuum back is invalidated before vacuum enters failsafe mode.
+ </para>
+
+ <para>
+ Note that this invalidation mechanism is not applicable for slots
+ on the standby server that are being synced from the primary server
+ (i.e., standby slots having
+ <link linkend="view-pg-replication-slots">pg_replication_slots</link>.<structfield>synced</structfield>
+ value <literal>true</literal>). Synced slots are always considered to
+ be inactive because they don't perform logical decoding to produce
+ changes.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry id="guc-wal-sender-timeout" xreflabel="wal_sender_timeout">
<term><varname>wal_sender_timeout</varname> (<type>integer</type>)
<indexterm>
diff --git a/doc/src/sgml/logical-replication.sgml b/doc/src/sgml/logical-replication.sgml
index 23b268273b9..a865a5e6c28 100644
--- a/doc/src/sgml/logical-replication.sgml
+++ b/doc/src/sgml/logical-replication.sgml
@@ -2649,7 +2649,9 @@ CONTEXT: processing remote data for replication origin "pg_16395" during "INSER
<para>
Logical replication slots are also affected by
- <link linkend="guc-idle-replication-slot-timeout"><varname>idle_replication_slot_timeout</varname></link>.
+ <link linkend="guc-idle-replication-slot-timeout"><varname>idle_replication_slot_timeout</varname></link>
+ and
+ <link linkend="guc-max-slot-xid-age"><varname>max_slot_xid_age</varname></link>.
</para>
<para>
diff --git a/doc/src/sgml/system-views.sgml b/doc/src/sgml/system-views.sgml
index 9ee1a2bfc6a..1a507b430f9 100644
--- a/doc/src/sgml/system-views.sgml
+++ b/doc/src/sgml/system-views.sgml
@@ -3102,6 +3102,14 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx
<xref linkend="guc-idle-replication-slot-timeout"/> duration.
</para>
</listitem>
+ <listitem>
+ <para>
+ <literal>xid_aged</literal> means that the slot's
+ <literal>xmin</literal> or <literal>catalog_xmin</literal>
+ has reached the age specified by
+ <xref linkend="guc-max-slot-xid-age"/> parameter.
+ </para>
+ </listitem>
</itemizedlist>
</para></entry>
</row>
diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c
index 88c71cd85b6..bf048167679 100644
--- a/src/backend/access/heap/vacuumlazy.c
+++ b/src/backend/access/heap/vacuumlazy.c
@@ -147,6 +147,7 @@
#include "pgstat.h"
#include "portability/instr_time.h"
#include "postmaster/autovacuum.h"
+#include "replication/slot.h"
#include "storage/bufmgr.h"
#include "storage/freespace.h"
#include "storage/latch.h"
@@ -799,6 +800,20 @@ heap_vacuum_rel(Relation rel, const VacuumParams *params,
* to increase the number of dead tuples it can prune away.)
*/
vacrel->aggressive = vacuum_get_cutoffs(rel, params, &vacrel->cutoffs);
+
+ /* Try to invalidate XID-aged replication slots */
+ if (MaybeInvalidateXIDAgedSlots(vacrel->cutoffs.OldestXmin,
+ vacrel->cutoffs.OldestSlotXmin,
+ vacrel->cutoffs.OldestSlotCatalogXmin))
+ {
+ /*
+ * Some slots have been invalidated; re-compute the vacuum cutoffs and
+ * aggresiveness.
+ */
+ vacrel->aggressive = vacuum_get_cutoffs(rel, params,
+ &vacrel->cutoffs);
+ }
+
vacrel->rel_pages = orig_rel_pages = RelationGetNumberOfBlocks(rel);
vacrel->vistest = GlobalVisTestFor(rel);
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 2c1c6f88b74..eac73091172 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -7019,6 +7019,8 @@ CreateCheckPoint(int flags)
VirtualTransactionId *vxids;
int nvxids;
int oldXLogAllowed = 0;
+ uint32 slotInvalidationCauses;
+ TransactionId slotXidLimit;
/*
* An end-of-recovery checkpoint is really a shutdown checkpoint, just
@@ -7447,9 +7449,20 @@ CreateCheckPoint(int flags)
*/
XLByteToSeg(RedoRecPtr, _logSegNo, wal_segment_size);
KeepLogSeg(recptr, &_logSegNo);
- if (InvalidateObsoleteReplicationSlots(RS_INVAL_WAL_REMOVED | RS_INVAL_IDLE_TIMEOUT,
+
+ slotInvalidationCauses = RS_INVAL_WAL_REMOVED | RS_INVAL_IDLE_TIMEOUT;
+ slotXidLimit = InvalidTransactionId;
+ if (max_slot_xid_age > 0)
+ {
+ slotInvalidationCauses |= RS_INVAL_XID_AGE;
+ slotXidLimit = TransactionIdRetreatedBy(ReadNextTransactionId(),
+ max_slot_xid_age);
+ }
+
+ if (InvalidateObsoleteReplicationSlots(slotInvalidationCauses,
_logSegNo, InvalidOid,
- InvalidTransactionId))
+ InvalidTransactionId,
+ slotXidLimit))
{
/*
* Some slots have been invalidated; recalculate the old-segment
@@ -7730,6 +7743,8 @@ CreateRestartPoint(int flags)
XLogRecPtr endptr;
XLogSegNo _logSegNo;
TimestampTz xtime;
+ uint32 slotInvalidationCauses;
+ TransactionId slotXidLimit;
/* Concurrent checkpoint/restartpoint cannot happen */
Assert(!IsUnderPostmaster || MyBackendType == B_CHECKPOINTER);
@@ -7904,9 +7919,19 @@ CreateRestartPoint(int flags)
INJECTION_POINT("restartpoint-before-slot-invalidation", NULL);
- if (InvalidateObsoleteReplicationSlots(RS_INVAL_WAL_REMOVED | RS_INVAL_IDLE_TIMEOUT,
+ slotInvalidationCauses = RS_INVAL_WAL_REMOVED | RS_INVAL_IDLE_TIMEOUT;
+ slotXidLimit = InvalidTransactionId;
+ if (max_slot_xid_age > 0)
+ {
+ slotInvalidationCauses |= RS_INVAL_XID_AGE;
+ slotXidLimit = TransactionIdRetreatedBy(ReadNextTransactionId(),
+ max_slot_xid_age);
+ }
+
+ if (InvalidateObsoleteReplicationSlots(slotInvalidationCauses,
_logSegNo, InvalidOid,
- InvalidTransactionId))
+ InvalidTransactionId,
+ slotXidLimit))
{
/*
* Some slots have been invalidated; recalculate the old-segment
@@ -8770,6 +8795,7 @@ xlog_redo(XLogReaderState *record)
*/
InvalidateObsoleteReplicationSlots(RS_INVAL_WAL_LEVEL,
0, InvalidOid,
+ InvalidTransactionId,
InvalidTransactionId);
}
else if (sync_replication_slots)
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 0ed363d1c85..2243a7dcb80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -1133,7 +1133,10 @@ vacuum_get_cutoffs(Relation rel, const VacuumParams *params,
* that only one vacuum process can be working on a particular table at
* any time, and that each vacuum is always an independent transaction.
*/
- cutoffs->OldestXmin = GetOldestNonRemovableTransactionId(rel);
+ cutoffs->OldestXmin =
+ GetOldestNonRemovableTransactionIdWithSlotXids(rel,
+ &cutoffs->OldestSlotXmin,
+ &cutoffs->OldestSlotCatalogXmin);
Assert(TransactionIdIsNormal(cutoffs->OldestXmin));
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index a9092fc2382..712f535090b 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -117,6 +117,7 @@ static const SlotInvalidationCauseMap SlotInvalidationCauses[] = {
{RS_INVAL_HORIZON, "rows_removed"},
{RS_INVAL_WAL_LEVEL, "wal_level_insufficient"},
{RS_INVAL_IDLE_TIMEOUT, "idle_timeout"},
+ {RS_INVAL_XID_AGE, "xid_aged"},
};
/*
@@ -158,6 +159,12 @@ int max_replication_slots = 10; /* the maximum number of replication
*/
int idle_replication_slot_timeout_secs = 0;
+/*
+ * Invalidate replication slots that have xmin or catalog_xmin older
+ * than the specified age; '0' disables it.
+ */
+int max_slot_xid_age = 0;
+
/*
* This GUC lists streaming replication standby server slot names that
* logical WAL sender processes will wait for.
@@ -1780,7 +1787,10 @@ ReportSlotInvalidation(ReplicationSlotInvalidationCause cause,
XLogRecPtr restart_lsn,
XLogRecPtr oldestLSN,
TransactionId snapshotConflictHorizon,
- long slot_idle_seconds)
+ long slot_idle_seconds,
+ TransactionId xmin,
+ TransactionId catalog_xmin,
+ TransactionId xidLimit)
{
StringInfoData err_detail;
StringInfoData err_hint;
@@ -1825,6 +1835,29 @@ ReportSlotInvalidation(ReplicationSlotInvalidationCause cause,
"idle_replication_slot_timeout");
break;
}
+
+ case RS_INVAL_XID_AGE:
+ {
+ TransactionId slot_xid = TransactionIdIsValid(xmin) ? xmin : catalog_xmin;
+ int32 exceeded_by = (int32) (xidLimit - slot_xid);
+ int32 slot_age = (int32) max_slot_xid_age + exceeded_by;
+
+ /* Either the slot's xmin or catalog_xmin must be valid */
+ Assert(TransactionIdIsValid(slot_xid));
+
+ /* translator: %s is a GUC variable name */
+ appendStringInfo(&err_detail,
+ TransactionIdIsValid(xmin)
+ ? _("The slot's xmin age of %d exceeds the configured \"%s\" of %d by %d transactions")
+ : _("The slot's catalog xmin age of %d exceeds the configured \"%s\" of %d by %d transactions"),
+ slot_age, "max_slot_xid_age", max_slot_xid_age, exceeded_by);
+
+ /* translator: %s is a GUC variable name */
+ appendStringInfo(&err_hint, _("You might need to increase \"%s\"."),
+ "max_slot_xid_age");
+ break;
+ }
+
case RS_INVAL_NONE:
pg_unreachable();
}
@@ -1863,6 +1896,25 @@ CanInvalidateIdleSlot(ReplicationSlot *s)
!(RecoveryInProgress() && s->data.synced));
}
+/*
+ * Can we invalidate an XID-aged replication slot?
+ *
+ * XID-aged based invalidation is allowed to the given slot when:
+ *
+ * 1. Max XID-age is set
+ * 2. Slot has valid xmin or catalog_xmin
+ * 3. The slot is not being synced from the primary while the server is in
+ * recovery.
+ */
+static inline bool
+CanInvalidateXidAgedSlot(ReplicationSlot *s)
+{
+ return (max_slot_xid_age != 0 &&
+ (TransactionIdIsValid(s->data.xmin) ||
+ TransactionIdIsValid(s->data.catalog_xmin)) &&
+ !(RecoveryInProgress() && s->data.synced));
+}
+
/*
* DetermineSlotInvalidationCause - Determine the cause for which a slot
* becomes invalid among the given possible causes.
@@ -1874,6 +1926,7 @@ static ReplicationSlotInvalidationCause
DetermineSlotInvalidationCause(uint32 possible_causes, ReplicationSlot *s,
XLogRecPtr oldestLSN, Oid dboid,
TransactionId snapshotConflictHorizon,
+ TransactionId xidLimit,
TimestampTz *inactive_since, TimestampTz now)
{
Assert(possible_causes != RS_INVAL_NONE);
@@ -1945,6 +1998,18 @@ DetermineSlotInvalidationCause(uint32 possible_causes, ReplicationSlot *s,
}
}
+ /* Check if the slot needs to be invalidated due to max_slot_xid_age GUC */
+ if ((possible_causes & RS_INVAL_XID_AGE) && CanInvalidateXidAgedSlot(s))
+ {
+ Assert(TransactionIdIsValid(xidLimit));
+
+ if ((TransactionIdIsValid(s->data.xmin) &&
+ TransactionIdPrecedes(s->data.xmin, xidLimit)) ||
+ (TransactionIdIsValid(s->data.catalog_xmin) &&
+ TransactionIdPrecedes(s->data.catalog_xmin, xidLimit)))
+ return RS_INVAL_XID_AGE;
+ }
+
return RS_INVAL_NONE;
}
@@ -1967,6 +2032,7 @@ InvalidatePossiblyObsoleteSlot(uint32 possible_causes,
ReplicationSlot *s,
XLogRecPtr oldestLSN,
Oid dboid, TransactionId snapshotConflictHorizon,
+ TransactionId xidLimit,
bool *released_lock_out)
{
int last_signaled_pid = 0;
@@ -2019,6 +2085,7 @@ InvalidatePossiblyObsoleteSlot(uint32 possible_causes,
s, oldestLSN,
dboid,
snapshotConflictHorizon,
+ xidLimit,
&inactive_since,
now);
@@ -2112,7 +2179,8 @@ InvalidatePossiblyObsoleteSlot(uint32 possible_causes,
ReportSlotInvalidation(invalidation_cause, true, active_pid,
slotname, restart_lsn,
oldestLSN, snapshotConflictHorizon,
- slot_idle_secs);
+ slot_idle_secs, s->data.xmin,
+ s->data.catalog_xmin, xidLimit);
if (MyBackendType == B_STARTUP)
(void) SignalRecoveryConflict(GetPGProcByNumber(active_proc),
@@ -2165,7 +2233,8 @@ InvalidatePossiblyObsoleteSlot(uint32 possible_causes,
ReportSlotInvalidation(invalidation_cause, false, active_pid,
slotname, restart_lsn,
oldestLSN, snapshotConflictHorizon,
- slot_idle_secs);
+ slot_idle_secs, s->data.xmin,
+ s->data.catalog_xmin, xidLimit);
/* done with this slot for now */
break;
@@ -2192,6 +2261,8 @@ InvalidatePossiblyObsoleteSlot(uint32 possible_causes,
* logical.
* - RS_INVAL_IDLE_TIMEOUT: has been idle longer than the configured
* "idle_replication_slot_timeout" duration.
+ * - RS_INVAL_XID_AGE: slot xid age is older than the configured
+ * "max_slot_xid_age" age.
*
* Note: This function attempts to invalidate the slot for multiple possible
* causes in a single pass, minimizing redundant iterations. The "cause"
@@ -2205,7 +2276,8 @@ InvalidatePossiblyObsoleteSlot(uint32 possible_causes,
bool
InvalidateObsoleteReplicationSlots(uint32 possible_causes,
XLogSegNo oldestSegno, Oid dboid,
- TransactionId snapshotConflictHorizon)
+ TransactionId snapshotConflictHorizon,
+ TransactionId xidLimit)
{
XLogRecPtr oldestLSN;
bool invalidated = false;
@@ -2244,7 +2316,7 @@ restart:
if (InvalidatePossiblyObsoleteSlot(possible_causes, s, oldestLSN,
dboid, snapshotConflictHorizon,
- &released_lock))
+ xidLimit, &released_lock))
{
Assert(released_lock);
@@ -3275,3 +3347,57 @@ WaitForStandbyConfirmation(XLogRecPtr wait_for_lsn)
ConditionVariableCancelSleep();
}
+
+/*
+ * Invalidate replication slots whose XID age exceeds max_slot_xid_age.
+ *
+ * The caller supplies oldest xmin along with the oldest slot xmin and oldest
+ * catalog xmin, all obtained from the same ComputeXidHorizons() call. We use them
+ * to avoid unnecessary work: if a replication slot is not what's holding back
+ * OldestXmin (e.g., a long-running transaction is), invalidating slots would
+ * not help. Even when a slot is holding back OldestXmin, we still skip the
+ * invalidation call if OldestXmin has not yet exceeded max_slot_xid_age.
+ *
+ * Returns true if at least one slot was invalidated.
+ */
+bool
+MaybeInvalidateXIDAgedSlots(TransactionId OldestXmin,
+ TransactionId OldestSlotXmin,
+ TransactionId OldestSlotCatalogXmin)
+{
+ TransactionId xidLimit;
+ bool slotHoldsOldestXminBack;
+
+ if (max_slot_xid_age == 0)
+ return false;
+
+ Assert(TransactionIdIsNormal(OldestXmin));
+
+ /*
+ * Check if a replication slot's xmin or catalog_xmin is what's holding
+ * back OldestXmin. If not, skip the unnecessary work.
+ */
+ slotHoldsOldestXminBack =
+ (TransactionIdIsValid(OldestSlotXmin) &&
+ TransactionIdEquals(OldestXmin, OldestSlotXmin)) ||
+ (TransactionIdIsValid(OldestSlotCatalogXmin) &&
+ TransactionIdEquals(OldestXmin, OldestSlotCatalogXmin));
+
+ if (!slotHoldsOldestXminBack)
+ return false;
+
+ xidLimit = TransactionIdRetreatedBy(ReadNextTransactionId(),
+ max_slot_xid_age);
+
+ /*
+ * A replication slot is holding back OldestXmin. Now check whether the
+ * slot holding it back has also exceeded the XID age.
+ */
+ if (TransactionIdPrecedes(OldestXmin, xidLimit))
+ return InvalidateObsoleteReplicationSlots(RS_INVAL_XID_AGE,
+ 0, InvalidOid,
+ InvalidTransactionId,
+ xidLimit);
+
+ return false;
+}
diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c
index cc207cb56e3..898ef4a0833 100644
--- a/src/backend/storage/ipc/procarray.c
+++ b/src/backend/storage/ipc/procarray.c
@@ -1937,6 +1937,31 @@ GlobalVisHorizonKindForRel(Relation rel)
return VISHORIZON_TEMP;
}
+/*
+ * A helper function to return the appropriate oldest non-removable
+ * TransactionId from the pre-computed horizons, based on the relation
+ * type.
+ */
+static pg_attribute_always_inline TransactionId
+GetOldestNonRemovableTransactionIdFromHorizons(ComputeXidHorizonsResult *horizons,
+ Relation rel)
+{
+ switch (GlobalVisHorizonKindForRel(rel))
+ {
+ case VISHORIZON_SHARED:
+ return horizons->shared_oldest_nonremovable;
+ case VISHORIZON_CATALOG:
+ return horizons->catalog_oldest_nonremovable;
+ case VISHORIZON_DATA:
+ return horizons->data_oldest_nonremovable;
+ case VISHORIZON_TEMP:
+ return horizons->temp_oldest_nonremovable;
+ }
+
+ /* just to prevent compiler warnings */
+ return InvalidTransactionId;
+}
+
/*
* Return the oldest XID for which deleted tuples must be preserved in the
* passed table.
@@ -1955,20 +1980,30 @@ GetOldestNonRemovableTransactionId(Relation rel)
ComputeXidHorizons(&horizons);
- switch (GlobalVisHorizonKindForRel(rel))
- {
- case VISHORIZON_SHARED:
- return horizons.shared_oldest_nonremovable;
- case VISHORIZON_CATALOG:
- return horizons.catalog_oldest_nonremovable;
- case VISHORIZON_DATA:
- return horizons.data_oldest_nonremovable;
- case VISHORIZON_TEMP:
- return horizons.temp_oldest_nonremovable;
- }
+ return GetOldestNonRemovableTransactionIdFromHorizons(&horizons, rel);
+}
- /* just to prevent compiler warnings */
- return InvalidTransactionId;
+/*
+ * Same as GetOldestNonRemovableTransactionId(), but also returns the
+ * replication slot xmin and catalog_xmin from the same ComputeXidHorizons()
+ * call. This avoids a separate ProcArrayLock acquisition when the caller
+ * needs both values.
+ */
+TransactionId
+GetOldestNonRemovableTransactionIdWithSlotXids(Relation rel,
+ TransactionId *slot_xmin,
+ TransactionId *slot_catalog_xmin)
+{
+ ComputeXidHorizonsResult horizons;
+
+ ComputeXidHorizons(&horizons);
+
+ if (slot_xmin)
+ *slot_xmin = horizons.slot_xmin;
+ if (slot_catalog_xmin)
+ *slot_catalog_xmin = horizons.slot_catalog_xmin;
+
+ return GetOldestNonRemovableTransactionIdFromHorizons(&horizons, rel);
}
/*
diff --git a/src/backend/storage/ipc/standby.c b/src/backend/storage/ipc/standby.c
index de9092fdf5b..d60f39ec08e 100644
--- a/src/backend/storage/ipc/standby.c
+++ b/src/backend/storage/ipc/standby.c
@@ -504,7 +504,8 @@ ResolveRecoveryConflictWithSnapshot(TransactionId snapshotConflictHorizon,
*/
if (IsLogicalDecodingEnabled() && isCatalogRel)
InvalidateObsoleteReplicationSlots(RS_INVAL_HORIZON, 0, locator.dbOid,
- snapshotConflictHorizon);
+ snapshotConflictHorizon,
+ InvalidTransactionId);
}
/*
diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat
index e556b8844d8..844ff8b5dea 100644
--- a/src/backend/utils/misc/guc_parameters.dat
+++ b/src/backend/utils/misc/guc_parameters.dat
@@ -2089,6 +2089,14 @@
max => 'MAX_KILOBYTES',
},
+{ name => 'max_slot_xid_age', type => 'int', context => 'PGC_SIGHUP', group => 'REPLICATION_SENDING',
+ short_desc => 'Age of the transaction ID at which a replication slot gets invalidated.',
+ variable => 'max_slot_xid_age',
+ boot_val => '0',
+ min => '0',
+ max => '2100000000',
+},
+
# We use the hopefully-safely-small value of 100kB as the compiled-in
# default for max_stack_depth. InitializeGUCOptions will increase it
# if possible, depending on the actual platform-specific stack limit.
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 2c5e98d1d4d..0038026a570 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -351,6 +351,8 @@
#wal_keep_size = 0 # in megabytes; 0 disables
#max_slot_wal_keep_size = -1 # in megabytes; -1 disables
#idle_replication_slot_timeout = 0 # in seconds; 0 disables
+#max_slot_xid_age = 0 # maximum XID age before a replication slot
+ # gets invalidated; 0 disables
#wal_sender_timeout = 60s # in milliseconds; 0 disables
#track_commit_timestamp = off # collect timestamp of transaction commit
# (change requires restart)
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 37631f700af..9ebc71fcac2 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -1901,7 +1901,7 @@ start_standby_server(const struct CreateSubscriberOptions *opt, bool restricted_
appendPQExpBufferStr(pg_ctl_cmd, " -s -o \"-c sync_replication_slots=off\"");
/* Prevent unintended slot invalidation */
- appendPQExpBufferStr(pg_ctl_cmd, " -o \"-c idle_replication_slot_timeout=0\"");
+ appendPQExpBufferStr(pg_ctl_cmd, " -o \"-c idle_replication_slot_timeout=0 -c max_slot_xid_age=0\"");
if (restricted_access)
{
diff --git a/src/include/commands/vacuum.h b/src/include/commands/vacuum.h
index 5b8023616c0..1a03336d6c0 100644
--- a/src/include/commands/vacuum.h
+++ b/src/include/commands/vacuum.h
@@ -287,6 +287,13 @@ struct VacuumCutoffs
*/
TransactionId FreezeLimit;
MultiXactId MultiXactCutoff;
+
+ /*
+ * Oldest xmin and catalog xmin of any replication slot obtained from the
+ * same ComputeXidHorizons() call that computed OldestXmin.
+ */
+ TransactionId OldestSlotXmin;
+ TransactionId OldestSlotCatalogXmin;
};
/*
diff --git a/src/include/replication/slot.h b/src/include/replication/slot.h
index 4b4709f6e2c..91f483024ce 100644
--- a/src/include/replication/slot.h
+++ b/src/include/replication/slot.h
@@ -66,10 +66,12 @@ typedef enum ReplicationSlotInvalidationCause
RS_INVAL_WAL_LEVEL = (1 << 2),
/* idle slot timeout has occurred */
RS_INVAL_IDLE_TIMEOUT = (1 << 3),
+ /* slot's xmin or catalog_xmin has reached max xid age */
+ RS_INVAL_XID_AGE = (1 << 4),
} ReplicationSlotInvalidationCause;
/* Maximum number of invalidation causes */
-#define RS_INVAL_MAX_CAUSES 4
+#define RS_INVAL_MAX_CAUSES 5
/*
* When the slot synchronization worker is running, or when
@@ -326,6 +328,7 @@ extern PGDLLIMPORT ReplicationSlot *MyReplicationSlot;
extern PGDLLIMPORT int max_replication_slots;
extern PGDLLIMPORT char *synchronized_standby_slots;
extern PGDLLIMPORT int idle_replication_slot_timeout_secs;
+extern PGDLLIMPORT int max_slot_xid_age;
/* shmem initialization functions */
extern Size ReplicationSlotsShmemSize(void);
@@ -367,7 +370,11 @@ extern void ReplicationSlotsDropDBSlots(Oid dboid);
extern bool InvalidateObsoleteReplicationSlots(uint32 possible_causes,
XLogSegNo oldestSegno,
Oid dboid,
- TransactionId snapshotConflictHorizon);
+ TransactionId snapshotConflictHorizon,
+ TransactionId xidLimit);
+extern bool MaybeInvalidateXIDAgedSlots(TransactionId OldestXmin,
+ TransactionId OldestSlotXmin,
+ TransactionId OldestSlotCatalogXmin);
extern ReplicationSlot *SearchNamedReplicationSlot(const char *name, bool need_lock);
extern int ReplicationSlotIndex(ReplicationSlot *slot);
extern bool ReplicationSlotName(int index, Name name);
diff --git a/src/include/storage/procarray.h b/src/include/storage/procarray.h
index abdf021e66e..a94091ce7fd 100644
--- a/src/include/storage/procarray.h
+++ b/src/include/storage/procarray.h
@@ -53,6 +53,9 @@ extern RunningTransactions GetRunningTransactionData(void);
extern bool TransactionIdIsInProgress(TransactionId xid);
extern TransactionId GetOldestNonRemovableTransactionId(Relation rel);
+extern TransactionId GetOldestNonRemovableTransactionIdWithSlotXids(Relation rel,
+ TransactionId *slot_xmin,
+ TransactionId *slot_catalog_xmin);
extern TransactionId GetOldestTransactionIdConsideredRunning(void);
extern TransactionId GetOldestActiveTransactionId(bool inCommitOnly,
bool allDbs);
diff --git a/src/test/recovery/t/019_replslot_limit.pl b/src/test/recovery/t/019_replslot_limit.pl
index 7b253e64d9c..8f0540a3c8b 100644
--- a/src/test/recovery/t/019_replslot_limit.pl
+++ b/src/test/recovery/t/019_replslot_limit.pl
@@ -540,4 +540,179 @@ is( $publisher4->safe_psql(
$publisher4->stop;
$subscriber4->stop;
+# Wait for the given slot to be invalidated with reason 'xid_aged'
+sub wait_for_xid_aged_invalidation
+{
+ my ($node, $slot_name) = @_;
+ $node->poll_query_until(
+ 'postgres', qq[
+ SELECT COUNT(slot_name) = 1 FROM pg_replication_slots
+ WHERE slot_name = '$slot_name' AND
+ active = false AND
+ invalidation_reason = 'xid_aged';
+ ]) or die "Timed out waiting for slot $slot_name to be invalidated";
+}
+
+# =====================================================================
+# Testcase start: Invalidate physical slot due to max_slot_xid_age GUC
+
+# Initialize primary node for XID age tests
+my $primary5 = PostgreSQL::Test::Cluster->new('primary5');
+$primary5->init(allows_streaming => 'logical');
+
+# Disable autovacuum so checkpointer triggers the invalidation
+my $max_slot_xid_age = 100;
+$primary5->append_conf(
+ 'postgresql.conf', qq{
+max_slot_xid_age = $max_slot_xid_age
+autovacuum = off
+});
+
+$primary5->start;
+
+# Create a procedure to consume XIDs
+$primary5->safe_psql(
+ 'postgres', qq{
+ CREATE PROCEDURE consume_xid(cnt int)
+ AS \$\$
+ DECLARE
+ i int;
+ BEGIN
+ FOR i IN 1..cnt LOOP
+ EXECUTE 'SELECT pg_current_xact_id()';
+ COMMIT;
+ END LOOP;
+ END;
+ \$\$ LANGUAGE plpgsql;
+});
+
+# Take a backup for creating standby
+$backup_name = 'backup5';
+$primary5->backup($backup_name);
+
+# Create standby with HS feedback so the slot gains an xmin
+my $standby5 = PostgreSQL::Test::Cluster->new('standby5');
+$standby5->init_from_backup($primary5, $backup_name, has_streaming => 1);
+$standby5->append_conf(
+ 'postgresql.conf', q{
+primary_slot_name = 'sb5_slot'
+hot_standby_feedback = on
+wal_receiver_status_interval = 1
+});
+$primary5->safe_psql(
+ 'postgres', qq[
+ SELECT pg_create_physical_replication_slot(slot_name := 'sb5_slot', immediately_reserve := true);
+]);
+$standby5->start;
+
+# Create some content on primary to move xmin
+$primary5->safe_psql('postgres',
+ "CREATE TABLE tab_int5 AS SELECT generate_series(1,10) AS a");
+$primary5->wait_for_catchup($standby5);
+
+# Wait for the physical slot to get xmin via hot_standby_feedback
+$primary5->poll_query_until(
+ 'postgres', qq[
+ SELECT xmin IS NOT NULL
+ FROM pg_catalog.pg_replication_slots
+ WHERE slot_name = 'sb5_slot';
+]) or die "Timed out waiting for slot sb5_slot xmin from HS feedback";
+
+# Stop standby so the slot becomes inactive with its xmin frozen
+$standby5->stop;
+
+# Advance XIDs past 2x max_slot_xid_age so the slot's xmin is stale enough
+$primary5->safe_psql('postgres', qq{CALL consume_xid(2 * $max_slot_xid_age)});
+$primary5->safe_psql('postgres', "CHECKPOINT");
+wait_for_xid_aged_invalidation($primary5, 'sb5_slot');
+ok(1, "physical slot invalidated due to XID age (via checkpoint)");
+
+# Testcase end: Invalidate physical slot due to max_slot_xid_age GUC
+# ===================================================================
+
+# ====================================================================
+# Testcase start: Invalidate logical slot due to max_slot_xid_age GUC
+
+# Create a logical slot directly on the primary (no subscriber needed).
+# The slot gets a catalog_xmin immediately upon creation.
+$primary5->safe_psql('postgres',
+ "SELECT pg_create_logical_replication_slot('lsub5_slot', 'pgoutput')");
+
+$primary5->poll_query_until(
+ 'postgres', qq[
+ SELECT catalog_xmin IS NOT NULL
+ FROM pg_catalog.pg_replication_slots
+ WHERE slot_name = 'lsub5_slot';
+]) or die "Timed out waiting for slot lsub5_slot catalog_xmin";
+
+# Advance XIDs past 2x max_slot_xid_age so the slot's catalog_xmin is stale enough
+$primary5->safe_psql('postgres', qq{CALL consume_xid(2 * $max_slot_xid_age)});
+
+# Vacuume a user table so OldestXmin does not include the slot's catalog_xmin,
+# skipping the invalidation of the slot.
+$primary5->safe_psql('postgres', "VACUUM tab_int5");
+is( $primary5->safe_psql(
+ 'postgres',
+ qq[SELECT invalidation_reason IS NULL FROM pg_replication_slots WHERE slot_name = 'lsub5_slot';]
+ ),
+ 't',
+ 'logical slot not invalidated after vacuuming a data table');
+
+# Vacuum a catalog table so OldestXmin includes the slot's catalog_xmin,
+# triggering invalidation of the slot.
+$primary5->safe_psql('postgres', "VACUUM pg_class");
+wait_for_xid_aged_invalidation($primary5, 'lsub5_slot');
+ok(1, "logical slot invalidated due to XID age (via vacuum)");
+
+# Testcase end: Invalidate logical slot due to max_slot_xid_age GUC
+# ==================================================================
+
+# ===============================================================================
+# Testcase start: Invalidate logical slot on standby due to max_slot_xid_age GUC
+
+# Disable max_slot_xid_age on primary and recreate the streaming slot
+$primary5->safe_psql(
+ 'postgres',
+ q{
+ALTER SYSTEM SET max_slot_xid_age = 0;
+SELECT pg_reload_conf();
+});
+$primary5->safe_psql('postgres',
+ "SELECT pg_drop_replication_slot('sb5_slot')");
+$primary5->safe_psql('postgres',
+ "SELECT pg_create_physical_replication_slot('sb5_slot', true)");
+$standby5->append_conf(
+ 'postgresql.conf', qq{
+max_slot_xid_age = $max_slot_xid_age
+autovacuum = off
+});
+$standby5->start;
+
+$primary5->wait_for_catchup($standby5);
+
+$standby5->create_logical_slot_on_standby($primary5, 'sb5_logical_slot',
+ 'postgres');
+
+$standby5->poll_query_until(
+ 'postgres', qq[
+ SELECT catalog_xmin IS NOT NULL
+ FROM pg_catalog.pg_replication_slots
+ WHERE slot_name = 'sb5_logical_slot';
+]) or die "Timed out waiting for sb5_logical_slot catalog_xmin";
+
+# Advance XIDs on primary, replay on standby, then restartpoint to invalidate
+$primary5->safe_psql('postgres', qq{CALL consume_xid(2 * $max_slot_xid_age)});
+$primary5->safe_psql('postgres', "CHECKPOINT");
+$primary5->wait_for_replay_catchup($standby5);
+$standby5->safe_psql('postgres', "CHECKPOINT");
+
+wait_for_xid_aged_invalidation($standby5, 'sb5_logical_slot');
+ok(1, "logical (standby) slot invalidated due to XID age (via restartpoint)");
+
+$standby5->stop;
+$primary5->stop;
+
+# Testcase end: Invalidate logical slot on standby due to max_slot_xid_age GUC
+# =============================================================================
+
done_testing();
--
2.47.3
[application/octet-stream] v9-0002-Add-more-tests-for-XID-age-slot-invalidation.patch (6.3K, 3-v9-0002-Add-more-tests-for-XID-age-slot-invalidation.patch)
download | inline diff:
From 3943d750a8883a2d20ae39ca8caa87fe5bf07971 Mon Sep 17 00:00:00 2001
From: Bharath Rupireddy <[email protected]>
Date: Fri, 3 Apr 2026 18:55:45 +0000
Subject: [PATCH v9 2/2] Add more tests for XID age slot invalidation
Consume XIDs up to wraparound WARNING limits with
max_slot_xid_age matching vacuum_failsafe_age (1.6B). Verify that
autovacuum invalidates the inactive replication slot
(XID-age-based invalidation), unblocks datfrozenxid advancement,
and prevents wraparound without any intervention.
---
src/test/recovery/Makefile | 3 +-
src/test/recovery/t/019_replslot_limit.pl | 130 ++++++++++++++++++++++
2 files changed, 132 insertions(+), 1 deletion(-)
diff --git a/src/test/recovery/Makefile b/src/test/recovery/Makefile
index d41aaaf8ae1..5c3d2c89941 100644
--- a/src/test/recovery/Makefile
+++ b/src/test/recovery/Makefile
@@ -12,7 +12,8 @@
EXTRA_INSTALL=contrib/pg_prewarm \
contrib/pg_stat_statements \
contrib/test_decoding \
- src/test/modules/injection_points
+ src/test/modules/injection_points \
+ src/test/modules/xid_wraparound
subdir = src/test/recovery
top_builddir = ../../..
diff --git a/src/test/recovery/t/019_replslot_limit.pl b/src/test/recovery/t/019_replslot_limit.pl
index 8f0540a3c8b..8ac5f1f699d 100644
--- a/src/test/recovery/t/019_replslot_limit.pl
+++ b/src/test/recovery/t/019_replslot_limit.pl
@@ -715,4 +715,134 @@ $primary5->stop;
# Testcase end: Invalidate logical slot on standby due to max_slot_xid_age GUC
# =============================================================================
+# =================================================================================
+# Testcase start: XID-age-based slot invalidation with autovacuum (production-like)
+
+# Standby sets slot xmin via HS feedback, disconnects, XIDs are consumed.
+# max_slot_xid_age is set to vacuum_failsafe_age (1.6B) so autovacuum
+# invalidates the slot before entering failsafe mode, unblocking
+# datfrozenxid advancement and avoiding XID wraparound without manual
+# VACUUM or downtime.
+
+# Verify server log shows slot invalidation by autovacuum worker
+sub verify_slot_xid_aged_invalidation_in_server_log
+{
+ my ($node, $slot_name, $max_age, $consumed_xids) = @_;
+
+ my $log = slurp_file($node->logfile);
+
+ # Verify the invalidation was performed by an autovacuum worker
+ like($log,
+ qr/autovacuum worker\[\d+\] LOG:\s+invalidating obsolete replication slot "$slot_name"/,
+ "server log: $slot_name invalidated by autovacuum worker");
+
+ # Verify DETAIL shows the xmin age exceeding max_slot_xid_age
+ like($log,
+ qr/autovacuum worker\[\d+\] DETAIL:\s+The slot's (?:catalog )?xmin age of (\d+) exceeds the configured "max_slot_xid_age" of $max_age by (\d+) transactions/,
+ "server log: DETAIL shows xmin age exceeds max_slot_xid_age $max_age");
+
+ # Extract xid age from the log and report for diagnostics
+ $log =~
+ /The slot's (?:catalog )?xmin age of (\d+) exceeds the configured "max_slot_xid_age" of $max_age by (\d+)/;
+ my $log_xid_age = $1 // 'N/A';
+ my $exceeded_by = $2 // 'N/A';
+ diag "xid_age from server log=$log_xid_age, exceeded_by=$exceeded_by, max_slot_xid_age=$max_age, consumed=$consumed_xids XIDs";
+}
+
+# Verify slot invalidation and wait for autovacuum to advance datfrozenxid
+sub verify_invalidation_and_recovery
+{
+ my ($node, $slot_name, $max_age, $consumed_xids) = @_;
+
+ return if $max_age == 0;
+
+ wait_for_xid_aged_invalidation($node, $slot_name);
+ ok(1, 'autovacuum invalidated slot due to xid_aged');
+
+ verify_slot_xid_aged_invalidation_in_server_log($node, $slot_name,
+ $max_age, $consumed_xids);
+
+ # Wait for autovacuum to advance datfrozenxid in all databases past the
+ # wraparound threshold.
+ $node->poll_query_until(
+ 'postgres', qq[
+ SELECT NOT EXISTS (
+ SELECT 1 FROM pg_database
+ WHERE age(datfrozenxid) > 2000000000
+ );
+ ]) or die "Timed out waiting for autovacuum to advance datfrozenxid in all databases";
+}
+
+my $primary6 = PostgreSQL::Test::Cluster->new('primary6');
+$primary6->init(allows_streaming => 'logical');
+
+$max_slot_xid_age = 1600000000; # matches vacuum_failsafe_age default
+$primary6->append_conf(
+ 'postgresql.conf', qq{
+max_slot_xid_age = $max_slot_xid_age
+autovacuum_naptime = 1s
+});
+
+$primary6->start;
+$primary6->safe_psql('postgres', "CREATE EXTENSION xid_wraparound");
+
+$backup_name = 'backup6';
+$primary6->backup($backup_name);
+
+my $standby6 = PostgreSQL::Test::Cluster->new('standby6');
+$standby6->init_from_backup($primary6, $backup_name, has_streaming => 1);
+$standby6->append_conf(
+ 'postgresql.conf', q{
+primary_slot_name = 'sb6_slot'
+hot_standby_feedback = on
+wal_receiver_status_interval = 1
+});
+
+$primary6->safe_psql('postgres',
+ "SELECT pg_create_physical_replication_slot('sb6_slot', true)");
+
+$standby6->start;
+
+$primary6->safe_psql('postgres',
+ "CREATE TABLE tab_int6 AS SELECT generate_series(1,10) AS a");
+$primary6->wait_for_catchup($standby6);
+
+$primary6->poll_query_until(
+ 'postgres', qq[
+ SELECT xmin IS NOT NULL FROM pg_replication_slots
+ WHERE slot_name = 'sb6_slot';
+]) or die "Timed out waiting for sb6_slot xmin from HS feedback";
+
+# Stop standby; slot xmin persists and holds back datfrozenxid
+$standby6->stop;
+
+# Consume XIDs in 50M chunks; autovacuum (naptime=1s) will invalidate the
+# slot once xmin age exceeds max_slot_xid_age.
+my $logstart6 = -s $primary6->logfile;
+my $chunk = 50_000_000;
+my $max_xids = 2_200_000_000;
+my $consumed = 0;
+
+while ($consumed < $max_xids)
+{
+ $primary6->safe_psql('postgres', "SELECT consume_xids($chunk)");
+ $consumed += $chunk;
+ my $remaining = $max_xids - $consumed;
+ diag "consumed $consumed / $max_xids XIDs ($remaining remaining)";
+}
+
+verify_invalidation_and_recovery($primary6, 'sb6_slot',
+ $max_slot_xid_age, $consumed);
+
+# Consume 1B more XIDs — combining with the 2.2B consumed above, the total
+# of 3.2B exceeds the 2^31 (~2.1B) usable XID space (xidStopLimit), i.e.
+# more than one full wraparound cycle, proving the system is healthy.
+$primary6->safe_psql('postgres', "SELECT consume_xids(1000000000)");
+ok(1, 'writes succeed after autovacuum invalidated the slot');
+
+$primary6->stop;
+
+# Testcase end: XID-age-based slot invalidation with autovacuum (production-like)
+# ================================================================================
+
done_testing();
--
2.47.3
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To: [email protected]
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Subject: Re: Introduce XID age based replication slot invalidation
In-Reply-To: <CALj2ACXR=5SoApm6duEOc6pi=-KaBqSxuSP6XNQot2LywrqtAA@mail.gmail.com>
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