Horton

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

Amit Kapila <amit.kapila16@gmail.com>

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From: Amit Kapila <amit.kapila16@gmail.com>
To: Peter Smith <smithpb2250@gmail.com>
Cc: Nisha Moond <nisha.moond412@gmail.com>, vignesh C <vignesh21@gmail.com>, Shlok Kyal <shlok.kyal.oss@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: 2025-02-10T09:45:07Z
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

On Mon, Feb 10, 2025 at 11:33 AM Peter Smith <smithpb2250@gmail.com> wrote:
>
> Some review comments for v72-0001.
>
> ======
> GENERAL
>
> My preference was to just keep the enum as per v70 for the *actual*
> cause, and introduce a separate set of bit flags for *possible* causes
> to be checked. This creates a clear code separation between the actual
> and possible. It also eliminates the need to jump through hoops just
> to map a cause to its name.
>
> You wrote:
>
> > OTOH, keeping the enums as they are in v70, and defining new macros
> for the very similar purpose could add unnecessary complexity to code
> management.
>
> Since both the enum and the bit flags would be defined in slot.h
> adjacent to each other I don't foresee much complexity. I concede, a
> dev might write code and accidentally muddle the enum instead of the
> flag  or vice versa but that's an example of sloppiness, not
> complexity. Certainly there would be fewer necessary changes than what
> are in the v72 patch due to all the cause/causename mappings. For
> example,
>
> slot.h - Now, introduces a NEW typedef SlotInvalidationCauseMap
> slot.h - Now, need extern for NEW function GetSlotInvalidationCauseName
>
> slot.c - Now, needed minor rewrite of GetSlotInvalidationCause instead
> of leaving it as-is
> slot.c - Now, needs a whole NEW looping function
> GetSlotInvalidationCauseName instead of direct array index.
>
> Several place now must call to the GetSlotInvalidationCauseName where
> previously a simple direct array lookup was done
> slot.c - NEW call in ReplicationSlotAcquire
> slotfuncs.c - NEW call in pg_get_replication_slots
>
> ~
>
> FWIW, I've attached a topup patch using my idea just to see what it
> might look like. The result was 20 lines less code.
>

I don't like the idea of maintaining the same information in two
different ways (as enum and bit flags). We already have a few cases of
defining bit flags as part of enums like ScanOptions and relopt_kind,
so I feel following that model would be a better approach.

-- 
With Regards,
Amit Kapila.