Re: Introduce XID age and inactive timeout based replication slot invalidation
Amit Kapila <amit.kapila16@gmail.com>
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Add a test for commit ac0e33136a using the injection point.
- 8a695d7998be 18.0 landed
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Invalidate inactive replication slots.
- ac0e33136abc 18.0 landed
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Fix incorrect slot type in BuildTupleHashTableExt
- d96d1d5152f3 18.0 cited
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Allow synced slots to have their inactive_since.
- 6f132ed693b6 17.0 landed
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Change last_inactive_time to inactive_since in pg_replication_slots.
- 6d49c8d4b4f4 17.0 landed
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Track last_inactive_time in pg_replication_slots.
- a11f330b5584 17.0 landed
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Track invalidation_reason in pg_replication_slots.
- 6ae701b4378d 17.0 landed
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Add option force_initdb to PostgreSQL::Test::Cluster:init()
- ff9e1e764fcc 17.0 cited
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Add a failover option to subscriptions.
- 776621a5e479 17.0 cited
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Allow setting failover property in the replication command.
- 73292404370c 17.0 cited
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Allow to enable failover property for replication slots via SQL API.
- c393308b69d2 17.0 cited
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Track conflict_reason in pg_replication_slots.
- 007693f2a3ac 17.0 cited
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Log messages for replication slot acquisition and release.
- 7c3fb505b14e 17.0 cited
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Remove vacuum_defer_cleanup_age
- 1118cd37eb61 16.0 cited
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Fix corruption due to vacuum_defer_cleanup_age underflowing 64bit xids
- be504a3e974d 16.0 cited
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meson: Add initial version of meson based build system
- e6927270cd18 16.0 cited
On Mon, Sep 16, 2024 at 3:31 PM Bharath Rupireddy
<bharath.rupireddyforpostgres@gmail.com> wrote:
>
> Please find the attached v46 patch having changes for the above review
> comments and your test review comments and Shveta's review comments.
>
-ReplicationSlotAcquire(const char *name, bool nowait)
+ReplicationSlotAcquire(const char *name, bool nowait, bool error_if_invalid)
{
ReplicationSlot *s;
int active_pid;
@@ -615,6 +620,22 @@ retry:
/* We made this slot active, so it's ours now. */
MyReplicationSlot = s;
+ /*
+ * An error is raised if error_if_invalid is true and the slot has been
+ * previously invalidated due to inactive timeout.
+ */
+ if (error_if_invalid &&
+ s->data.invalidated == RS_INVAL_INACTIVE_TIMEOUT)
+ {
+ Assert(s->inactive_since > 0);
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("can no longer get changes from replication slot \"%s\"",
+ NameStr(s->data.name)),
+ errdetail("This slot has been invalidated because it was inactive
for longer than the amount of time specified by \"%s\".",
+ "replication_slot_inactive_timeout")));
+ }
Why raise the ERROR just for timeout invalidation here and why not if
the slot is invalidated for other reasons? This raises the question of
what happens before this patch if the invalid slot is used from places
where we call ReplicationSlotAcquire(). I did a brief code analysis
and found that for StartLogicalReplication(), even if the error won't
occur in ReplicationSlotAcquire(), it would have been caught in
CreateDecodingContext(). I think that is where we should also add this
new error. Similarly, pg_logical_slot_get_changes_guts() and other
logical replication functions should be calling
CreateDecodingContext() which can raise the new ERROR. I am not sure
about how the invalid slots are handled during physical replication,
please check the behavior of that before this patch.
--
With Regards,
Amit Kapila.