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

Bertrand Drouvot <bertranddrouvot.pg@gmail.com>

From: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
To: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Cc: Amit Kapila <amit.kapila16@gmail.com>, Nathan Bossart <nathandbossart@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2024-03-26T09:42:40Z
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,

On Tue, Mar 26, 2024 at 02:27:17PM +0530, Bharath Rupireddy wrote:
> Please use the v22 patch set.

Thanks!

1 ===

+reset_synced_slots_info(void)

I'm not sure "reset" is the right word, what about slot_sync_shutdown_update()?

2 ===

+       for (int i = 0; i < max_replication_slots; i++)
+       {
+               ReplicationSlot *s = &ReplicationSlotCtl->replication_slots[i];
+
+               /* Check if it is a synchronized slot */
+               if (s->in_use && s->data.synced)
+               {
+                       TimestampTz now;
+
+                       Assert(SlotIsLogical(s));
+                       Assert(s->active_pid == 0);
+
+                       /*
+                        * Set the time since the slot has become inactive after shutting
+                        * down slot sync machinery. This helps correctly interpret the
+                        * time if the standby gets promoted without a restart. We get the
+                        * current time beforehand to avoid a system call while holding
+                        * the lock.
+                        */
+                       now = GetCurrentTimestamp();

What about moving "now = GetCurrentTimestamp()" outside of the for loop? (it
would be less costly and probably good enough).

Regards,

-- 
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
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