Re: pgstat_send_connstats() introduces unnecessary timestamp and UDP overhead
Andres Freund <andres@anarazel.de>
From: Andres Freund <andres@anarazel.de>
To: pgsql-hackers@lists.postgresql.org, Michael Paquier <michael@paquier.xyz>,
Laurenz Albe <laurenz.albe@cybertec.at>
Cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>, magnus@hagander.net,
pgsql-hackers@postgresql.org
Date: 2021-09-01T01:55:58Z
Lists: pgsql-hackers
Hi, On August 31, 2021 6:33:15 PM PDT, Michael Paquier <michael@paquier.xyz> wrote: >On Tue, Aug 31, 2021 at 04:55:35AM +0200, Laurenz Albe wrote: >> In the view of that, how about doubling PGSTAT_STAT_INTERVAL to 1000 >> milliseconds? That would mean slightly less up-to-date statistics, but >> I doubt that that will be a problem. And it should even out the increase >> in statistics messages, except in the case of lots of short-lived >> sessions. But in that scenario you cannot have session statistics >> without lots of extra messages, and such a workload has enough performance >> problems as it is, so I don't think we have to specifically worry about it. > >Perhaps we could do that. Now, increasing an interval for the sake of >balancing the extra load created by a feature while impacting the >whole set of stats is not really appealing. I think it's not helpful. Still increases the number of messages substantially in workloads with a lot of connections doing occasional queries. Which is common. Andres -- Sent from my Android device with K-9 Mail. Please excuse my brevity.
Commits
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Fix performance regression from session statistics.
- 7890a423470b 14.0 landed
- 37a9aa659111 15.0 landed
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Add pg_stat_database counters for sessions and session time
- 960869da0803 14.0 cited