Log details for stats dropped more than once

Bertrand Drouvot <bertranddrouvot.pg@gmail.com>

From: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
To: pgsql-hackers@lists.postgresql.org
Date: 2024-05-14T10:07:14Z
Lists: pgsql-hackers

Attachments

Hi hackers,

While resuming the work on refilenode stats (mentioned in [1] but did not share
the patch yet), I realized that my current POC patch is buggy enough to produce
things like:

024-05-14 09:51:14.783 UTC [1788714] FATAL:  can only drop stats once

While the CONTEXT provides the list of dropped stats:

2024-05-14 09:51:14.783 UTC [1788714] CONTEXT:  WAL redo at 0/D75F478 for Transaction/ABORT: 2024-05-14 09:51:14.782223+00; dropped stats: 2/16384/27512/0 2/16384/27515/0 2/16384/27516/0

It's not clear which one generates the error (don't pay attention to the actual
values, the issue comes from the new refilenode stats that I removed from the
output).

Attached a tiny patch to report the stat that generates the error. The patch uses
errdetail_internal() as the extra details don't seem to be useful to average
users.

[1]: https://www.postgresql.org/message-id/ZbIdgTjR2QcFJ2mE%40ip-10-97-1-34.eu-west-3.compute.internal

Looking forward to your feedback,

Regards

-- 
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com

Commits

  1. Add more debugging information when dropping twice pgstats entry