Horton

Re: Something is wrong with wal_compression

Andres Freund <andres@anarazel.de>

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From: Andres Freund <andres@anarazel.de>
To: Thomas Munro <thomas.munro@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Michael Paquier <michael@paquier.xyz>, Andrey Borodin <amborodin86@gmail.com>, Justin Pryzby <pryzby@telsasoft.com>, pgsql-hackers@lists.postgresql.org
Date: 2023-01-28T02:57:58Z
Lists: pgsql-hackers 
Hi,

On 2023-01-27 16:15:08 +1300, Thomas Munro wrote:
> It would be pg_current_xact_id() that would have to pay the cost of
> the WAL flush, not pg_xact_status() itself, but yeah that's what the
> patch does (with some optimisations).  I guess one question is whether
> there are any other reasonable real world uses of
> pg_current_xact_id(), other than the original goal[1].

txid_current() is a lot older than pg_current_xact_id(), and they're backed by
the same code afaict. 8.4 I think.

Unfortunately txid_current() is used in plenty montiring setups IME.

I don't think it's a good idea to make a function that was quite cheap for 15
years, suddenly be several orders of magnitude more expensive...

Greetings,

Andres Freund

Commits

  1. Remove recovery test 011_crash_recovery.pl

  2. Add a txid_status function.