Re: Possible missing segments in archiving on standby

From: Fujii Masao <masao(dot)fujii(at)oss(dot)nttdata(dot)com>
To: Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com>
Cc: pgsql-hackers(at)lists(dot)postgresql(dot)org
Subject: Re: Possible missing segments in archiving on standby
Date: 2021-09-08 13:41:43
Message-ID: a616c7d4-a6b7-4643-55f8-234f3832492c@oss.nttdata.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 2021/09/08 16:40, Kyotaro Horiguchi wrote:
> No. The discussion taken there is not about permanently missing .ready
> files, but about .ready files created out-of-order. So I don't think
> the outcome from the thread does *fix* this issue.

Hmm...

> I don't think we want such extent of perfectness at all for the case
> where some archive-related parameters are changed after a
> crash. Anyway we need to take a backup after that and at least all
> segments required for the backup will be properly archived. The
> segments up to the XLOG_SWITCH segment are harmless garbage, or a bit
> of food for disk.

So probably we reached the consensus that something like the attached patch
(XLogArchiveCheckDone_walfile_xlog_switch.patch) is enough for the corner
case where walreceiver fails to create .ready file of WAL file including
XLOG_SWITCH?

> Sounds convincing. Ok, I agree to that.

So barring any objection, I will commit the patch
and back-patch it to all supported version.

walreceiver_notify_archive_soon_v5.patch
walreceiver_notify_archive_soon_v5_pg14-13.patch
walreceiver_notify_archive_soon_v5_pg12-11.patch
walreceiver_notify_archive_soon_v5_pg10.patch
walreceiver_notify_archive_soon_v5_pg96.patch

Regards,

--
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION

Attachment Content-Type Size
XLogArchiveCheckDone_walfile_xlog_switch.patch text/plain 1.3 KB
walreceiver_notify_archive_soon_v5_pg10.patch text/plain 4.1 KB
walreceiver_notify_archive_soon_v5_pg12-11.patch text/plain 4.2 KB
walreceiver_notify_archive_soon_v5_pg14-13.patch text/plain 4.2 KB
walreceiver_notify_archive_soon_v5_pg96.patch text/plain 4.1 KB
walreceiver_notify_archive_soon_v5.patch text/plain 4.1 KB

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Amul Sul 2021-09-08 13:44:54 Re: [Patch] ALTER SYSTEM READ ONLY
Previous Message Tom Lane 2021-09-08 13:14:34 Re: Non-decimal integer literals