Re: Introduce XID age and inactive timeout based replication slot invalidation

Peter Smith <smithpb2250@gmail.com>

From: Peter Smith <smithpb2250@gmail.com>
To: Nisha Moond <nisha.moond412@gmail.com>
Cc: Amit Kapila <amit.kapila16@gmail.com>, vignesh C <vignesh21@gmail.com>, "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, shveta malik <shveta.malik@gmail.com>, Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>, Ajin Cherian <itsajin@gmail.com>, Bertrand Drouvot <bertranddrouvot.pg@gmail.com>, Masahiko Sawada <sawada.mshk@gmail.com>, Nathan Bossart <nathandbossart@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2025-01-31T05:09:46Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Add a test for commit ac0e33136a using the injection point.

  2. Invalidate inactive replication slots.

  3. Fix incorrect slot type in BuildTupleHashTableExt

  4. Allow synced slots to have their inactive_since.

  5. Change last_inactive_time to inactive_since in pg_replication_slots.

  6. Track last_inactive_time in pg_replication_slots.

  7. Track invalidation_reason in pg_replication_slots.

  8. Add option force_initdb to PostgreSQL::Test::Cluster:init()

  9. Add a failover option to subscriptions.

  10. Allow setting failover property in the replication command.

  11. Allow to enable failover property for replication slots via SQL API.

  12. Track conflict_reason in pg_replication_slots.

  13. Log messages for replication slot acquisition and release.

  14. Remove vacuum_defer_cleanup_age

  15. Fix corruption due to vacuum_defer_cleanup_age underflowing 64bit xids

  16. meson: Add initial version of meson based build system

Hi Nisha.

Here are some review comments for patch v65-0002

======
src/backend/replication/slot.c

ReportSlotInvalidation:

1.
+
+ case RS_INVAL_IDLE_TIMEOUT:
+ Assert(inactive_since > 0);
+ /* translator: second %s is a GUC variable name */
+ appendStringInfo(&err_detail,
+ _("The slot has remained idle since %s, which is longer than the
configured \"%s\" duration."),
+ timestamptz_to_str(inactive_since),
+ "idle_replication_slot_timeout");
+ break;
+

errdetail:

I guess it is no fault of this patch because I see you've only copied
nearby code, but AFAICT this function is still having an each-way bet
by using a mixture of _() macro which is for strings intended be
translated, but then only using them in errdetail_internal() which is
for strings that are NOT intended to be translated. Isn't it
contradictory? Why don't we use errdetail() here?

errhint:

Also, the way the 'hint' is implemented can only be meaningful for
RS_INVAL_WAL_REMOVED. This is also existing code that IMO it was
always strange, but now that this patch has added another kind of
switch (cause) this hint implementation now looks increasingly hacky
to me; it is also inflexible -- e.g. if you ever wanted to add
different hints. A neater implementation would be to make the code
more like how the err_detail is handled, so then the errhint string
would only be assigned within the "case RS_INVAL_WAL_REMOVED:"

======
Kind Regards,
Peter Smith.
Fujitsu Australia