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: 2025-01-02T00:13:38Z
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.

My review comments for patch v58-0001.

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

InvalidatePossiblyObsoleteSlot:

1.
  /*
- * If the slot can be acquired, do so and mark it invalidated
- * immediately.  Otherwise we'll signal the owning process, below, and
- * retry.
+ * If the slot can be acquired, do so and mark it as invalidated. If
+ * the slot is already ours, mark it as invalidated. Otherwise, we'll
+ * signal the owning process below and retry.
  */
- if (active_pid == 0)
+ if (active_pid == 0 ||
+ (MyReplicationSlot == s && active_pid == MyProcPid))
  {

As you previously explained [1] "This change applies to all types of
invalidation, not just inactive_timeout case [...] It's a general
optimization for the case when the current process is the active PID
for the slot."

In that case, should this be in a separate patch that can be pushed to
master by itself, i.e. independent of anything else in this thread
that is being done for the purpose of implementing the timeout
feature?

======
[1] https://www.postgresql.org/message-id/CABdArM5tcYTQ2zeAPWTciTnea4jj6sPUjVY9M1O-4wWoTBjFgw%40mail.gmail.com

Kind Regards,
Peter Smith.
Fujitsu Austalia