Horton

Re: Synchronizing slots from primary to standby

Amit Kapila <amit.kapila16@gmail.com>

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From: Amit Kapila <amit.kapila16@gmail.com>
To: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Cc: shveta malik <shveta.malik@gmail.com>, Masahiko Sawada <sawada.mshk@gmail.com>, "Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>, Peter Smith <smithpb2250@gmail.com>, Ajin Cherian <itsajin@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, Nisha Moond <nisha.moond412@gmail.com>, "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>, Bruce Momjian <bruce@momjian.us>, Ashutosh Sharma <ashu.coek88@gmail.com>, Andres Freund <andres@anarazel.de>, pgsql-hackers <pgsql-hackers@postgresql.org>, Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: 2024-02-22T11:53:59Z
Lists: pgsql-hackers 
On Thu, Feb 22, 2024 at 4:35 PM Bertrand Drouvot
<bertranddrouvot.pg@gmail.com> wrote:
>
> On Thu, Feb 22, 2024 at 04:01:34PM +0530, shveta malik wrote:
> > On Thu, Feb 22, 2024 at 3:44 PM Bertrand Drouvot
> > <bertranddrouvot.pg@gmail.com> wrote:
> > >
> > > Hi,
> > >
> > > Thanks!
> > >
> > > Some random comments about v92_001 (Sorry if it has already been discussed
> > > up-thread):
> >
> > Thanks for the feedback. The patch is pushed 15 minutes back.
>
> Yeah, saw that after I send the comments ;-)
>

There is a BF failure. See
https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=prion&dt=2024-02-22%2010%3A13%3A03.

The initial analysis suggests that for some reason, the primary went
down after the slot sync worker was invoked the first time. See the
below in the primary's LOG:

2024-02-22 10:59:56.896 UTC [2721639:29] standby1_slotsync worker LOG:
 00000: statement: SELECT slot_name, plugin, confirmed_flush_lsn,
restart_lsn, catalog_xmin, two_phase, failover, database,
conflict_reason FROM pg_catalog.pg_replication_slots WHERE failover
and NOT temporary
2024-02-22 10:59:56.896 UTC [2721639:30] standby1_slotsync worker
LOCATION:  exec_simple_query, postgres.c:1070
2024-02-22 11:00:26.967 UTC [2721639:31] standby1_slotsync worker LOG:
 00000: statement: SELECT slot_name, plugin, confirmed_flush_lsn,
restart_lsn, catalog_xmin, two_phase, failover, database,
conflict_reason FROM pg_catalog.pg_replication_slots WHERE failover
and NOT temporary
2024-02-22 11:00:26.967 UTC [2721639:32] standby1_slotsync worker
LOCATION:  exec_simple_query, postgres.c:1070
2024-02-22 11:00:35.908 UTC [2721435:309] LOG:  00000: received
immediate shutdown request
2024-02-22 11:00:35.908 UTC [2721435:310] LOCATION:
process_pm_shutdown_request, postmaster.c:2859
2024-02-22 11:00:35.911 UTC [2721435:311] LOG:  00000: database system
is shut down
2024-02-22 11:00:35.911 UTC [2721435:312] LOCATION:  UnlinkLockFiles,
miscinit.c:1138


-- 
With Regards,
Amit Kapila.

Commits

  1. Doc: Add the new section "Logical Replication Failover".

  2. Fix the review comments and a bug in the slot sync code.

  3. Fix a test in failover slots regression test.

  4. Fix the intermittent buildfarm failures in 040_standby_failover_slots_sync.

  5. Split XLogCtl->LogwrtResult into separate struct members

  6. Ensure that the sync slots reach a consistent state after promotion without losing data.

  7. Introduce a new GUC 'standby_slot_names'.

  8. Fix BF failure introduced by commit b3f6b14cf4.

  9. Fixups for commit 93db6cbda0.

  10. Fix BF failure in commit 93db6cbda0.

  11. Add a new slot sync worker to synchronize logical slots.

  12. Improve ERROR/LOG messages added by commits ddd5f4f54a and 7a424ece48.

  13. Disable autovacuum on primary in 040_standby_failover_slots_sync test.

  14. Fix the incorrect format specifier used in commit 7a424ece48.

  15. Change the LOG level in 040_standby_failover_slots_sync.pl to DEBUG2.

  16. Add more LOG and DEBUG messages for slot synchronization.

  17. Another try to fix BF failure introduced in commit ddd5f4f54a.

  18. Fix BF introduced in commit ddd5f4f54a.

  19. Add a slot synchronization function.

  20. Clean-ups for 776621a5e4 and 7329240437.

  21. Enhance libpqrcv APIs to support slot synchronization.

  22. Add a failover option to subscriptions.

  23. Allow setting failover property in the replication command.

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

  25. Add macros for looping through a List without a ListCell.

  26. Track conflict_reason in pg_replication_slots.

  27. Allow upgrades to preserve the full subscription's state.

  28. Add support for incremental backup.

  29. Simplify some logic in CreateReplicationSlot()

  30. Fix uninitialized access to InitialRunningXacts during decoding after ERROR.

  31. Flexible options for CREATE_REPLICATION_SLOT.

  32. Empty search_path in logical replication apply worker and walsender.

  33. Fix oldest xmin and LSN computation across repslots after advancing

  34. Require C99 (and thus MSCV 2013 upwards).