Horton

Re: Race condition in recovery?

Dilip Kumar <dilipbalaut@gmail.com>

View thread View on postgr.es
From: Dilip Kumar <dilipbalaut@gmail.com>
To: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Cc: Robert Haas <robertmhaas@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2021-05-10T08:57:21Z
Lists: pgsql-hackers 
On Mon, May 10, 2021 at 2:05 PM Kyotaro Horiguchi
<horikyota.ntt@gmail.com> wrote:

> I thought that the reason using receiveTLI instead of
> recoveryTargetTLI here is that there's a case where receiveTLI is the
> future of recoveryTarrgetTLI but I haven't successfully had such a
> situation.  If I set recovoryTargetTLI to a TLI that standby doesn't
> know but primary knows, validateRecoveryParameters immediately
> complains about that before reaching there.  Anyway the attached
> assumes receiveTLI may be the future of recoveryTargetTLI.

If you see the note in this commit. It says without the timeline
history file, so does it trying to say that although receiveTLI is the
ancestor of recovoryTargetTLI,  it can not detect that because of the
absence of the TL.history file ?

ee994272ca50f70b53074f0febaec97e28f83c4e
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>  2013-01-03 14:11:58
Committer: Heikki Linnakangas <heikki.linnakangas@iki.fi>  2013-01-03 14:11:58
.....
  Without the timeline history file, recovering that file
    will fail as the older timeline ID is not recognized to be an ancestor of
    the target timeline. If you try to recover from such a backup, using only
    streaming replication to fetch the WAL, this patch is required for that to
    work.
=====

>
> I believe the 004_timeline_switch.pl detects your issue.  And the
> attached change fixes it.

I think this fix looks better to me, but I will think more about it
and give my feedback.  Thanks for quickly coming up with the
reproducible test case.


-- 
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com

Commits

  1. Further refinement of stuck_on_old_timeline recovery test

  2. Adjust new test case to set wal_keep_segments.

  3. Adjust new test case to set wal_keep_size.

  4. Fix corner case failure of new standby to follow new primary.

  5. Back-port a few PostgresNode.pm methods.

  6. Allow PostgresNode.pm's backup method to accept backup_options.

  7. Add end-to-end testing of pg_basebackup's tar-format output.

  8. Allow PostgresNode.pm tests to wait for catchup

  9. Delay reading timeline history file until it's fetched from master.