Re: Introduce XID age and inactive timeout based replication slot invalidation - Mailing list pgsql-hackers

From shveta malik
Subject Re: Introduce XID age and inactive timeout based replication slot invalidation
Date
Msg-id CAJpy0uB48aCJX8gpwwv-kGoOK3WYXWatB=1pgr__UW-OjwKkDg@mail.gmail.com
Whole thread Raw
In response to Re: Introduce XID age and inactive timeout based replication slot invalidation  (shveta malik <shveta.malik@gmail.com>)
List pgsql-hackers
On Wed, Sep 18, 2024 at 3:31 PM shveta malik <shveta.malik@gmail.com> wrote:
>
> On Wed, Sep 18, 2024 at 2:49 PM shveta malik <shveta.malik@gmail.com> wrote:
> >
> > > > Please find the attached v46 patch having changes for the above review
> > > > comments and your test review comments and Shveta's review comments.
> > > >
>

When we promote hot standby with synced logical slots to become new
primary, the logical slots are never invalidated with
'inactive_timeout' on new primary.  It seems the check in
SlotInactiveTimeoutCheckAllowed() is wrong. We should allow
invalidation of slots on primary even if they are marked as 'synced'.
Please see [4].
I have raised 4 issues so far on v46, the first 3 are in [1],[2],[3].
Once all these are addressed, I can continue reviewing further.

[1]: https://www.postgresql.org/message-id/CAJpy0uAwxc49Dz6t%3D-y_-z-MU%2BA4RWX4BR3Zri_jj2qgGMq_8g%40mail.gmail.com
[2]: https://www.postgresql.org/message-id/CAJpy0uC6nN3SLbEuCvz7-CpaPdNdXxH%3DfeW5MhYQch-JWV0tLg%40mail.gmail.com
[3]: https://www.postgresql.org/message-id/CAJpy0uBXXJC6f04%2BFU1axKaU%2Bp78wN0SEhUNE9XoqbjXj%3Dhhgw%40mail.gmail.com

[4]:
--------------------
postgres=#  select pg_is_in_recovery();
--------
 f

postgres=# show replication_slot_inactive_timeout;
 replication_slot_inactive_timeout
-----------------------------------
 10s

postgres=# select slot_name, inactive_since, invalidation_reason,
synced from pg_replication_slots;
  slot_name  |          inactive_since          | invalidation_reason | synced
-------------+----------------------------------+---------------------+----------+--------
 mysubnew1_1 | 2024-09-19 09:04:09.714283+05:30 |                     | t

postgres=# select now();
               now
----------------------------------
 2024-09-19 09:06:28.871354+05:30

postgres=# checkpoint;
CHECKPOINT

postgres=# select slot_name, inactive_since, invalidation_reason,
synced from pg_replication_slots;
  slot_name  |          inactive_since          | invalidation_reason | synced
-------------+----------------------------------+---------------------+----------+--------
 mysubnew1_1 | 2024-09-19 09:04:09.714283+05:30 |                     | t
--------------------

thanks
Shveta



pgsql-hackers by date:

Previous
From: Amit Kapila
Date:
Subject: Re: Using per-transaction memory contexts for storing decoded tuples
Next
From: Tatsuo Ishii
Date:
Subject: Re: Add memory/disk usage for WindowAgg nodes in EXPLAIN