Re: Rework SLRU I/O errors handle
Heikki Linnakangas <hlinnaka@iki.fi>
From: Heikki Linnakangas <hlinnaka@iki.fi>
To: Maxim Orlov <orlovmg@gmail.com>
Cc: Álvaro Herrera <alvherre@kurilemu.de>, Postgres hackers <pgsql-hackers@lists.postgresql.org>
Date: 2026-03-11T10:51:53Z
Lists: pgsql-hackers
Attachments
- v5-0001-Add-a-callback-for-I-O-error-messages-in-SLRUs.patch (text/x-patch) patch v5-0001
- v5-0002-make-the-errdetail-on-multixact-members-more-deta.patch (text/x-patch) patch v5-0002
On 06/03/2026 19:08, Maxim Orlov wrote: > I don't know what's happening with my mail, but I haven't > received the previous letters. > > Anyway, v4 looks good to me. > Perhaps the extra double line following clog_errdetail_for_io_error > is unnecessary? But as always, to your taste. Thanks. I did one more iteration on this: I realized that the error we now printed for errors on pg_multixact/members always printed the failing offset, whereas before this patch we usually printed the failing *multixid* that the member is part of. Printing the multixid might actually be more useful; the offset can more easily be deduced from the segment filename and physical offset that is printed anyway, but it's harder to know which multixid it belongs to. This printing the originating multixid seems useful. If things go badly wrong and you need to do manual debugging of a corrupted database, the multixid can more easily be compared with the xmax in the heap and with pg_waldump output, for example. We can print both, per attached, which is even better. This is perhaps overkill, but then again, if you hit an error like this, you really appreciate any extra information you can get. - Heikki
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Add callback for I/O error messages in SLRUs
- f9de9bf302d2 19 (unreleased) landed