Horton

Re: Add new option 'all' to pg_stat_reset_shared()

Andres Freund <andres@anarazel.de>

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From: Andres Freund <andres@anarazel.de>
To: Michael Paquier <michael@paquier.xyz>
Cc: torikoshia <torikoshia@oss.nttdata.com>, Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>, boekewurm+postgres@gmail.com, Kyotaro Horiguchi <horikyota.ntt@gmail.com>, pgsql-hackers@postgresql.org
Date: 2023-11-09T01:29:52Z
Lists: pgsql-hackers 
Hi,

On 2023-11-09 10:25:18 +0900, Michael Paquier wrote:
> On Thu, Nov 09, 2023 at 10:10:39AM +0900, torikoshia wrote:
> > I am a little concerned about that the reset time is not the same and that
> > GetCurrentTimestamp() is called multiple times, but I think it would be
> > acceptable because the function is probably not used that often and the
> > reset time is not atomic in practice.
> 
> Arf, right.  I misremembered that this is just a clock_timestamp() so
> that's not transaction-resilient.  Anyway, my take is that this is not
> a big deal in practice compared to the usability of the wrapper.

It seems inconsequential cost-wise. Resetting stats is way more expensive that
a few timestamp determinations. Correctness wise it actually seems *better* to
record the timestamps more granularly, after all, that moves them closer to
the time the individual kind of stats is reset.

Greetings,

Andres Freund

Commits

  1. Add target "slru" to pg_stat_reset_shared()

  2. doc: Improve description of targets for pg_stat_reset_shared()

  3. Add support for pg_stat_reset_slru without argument

  4. Add ability to reset all shared stats types in pg_stat_reset_shared()