Message-ID: <d7a858f9-404f-4535-8160-3222e43cf8c5@oss.nttdata.com>
Date: Thu, 17 Oct 2024 01:59:10 +0900
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Subject: Re: [BUGS] BUG #10123: Weird entries in pg_stat_activity
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To: Andres Freund <andres@anarazel.de>
Cc: Fujii Masao <masao.fujii@gmail.com>, maxim.boguk@gmail.com,
 pgsql-bugs@postgresql.org
References: <20140424101827.2714.39486@wrigleys.postgresql.org>
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 <2153c106-8979-430d-ba86-34d35e565ab4@oss.nttdata.com>
 <20240704220316.srzqzkb7zgzh76xy@alap3.anarazel.de>
From: Fujii Masao <masao.fujii@oss.nttdata.com>
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On 2024/07/05 7:03, Andres Freund wrote:
> Calls to pgstat_report_activity() aren't exactly free. This substantially
> increases the number of calls to it for common workloads. There got to be a
> more targeted way of dealing with this.

Yes. So, as an alternative approach, how about setting xact_start and
query_start to NULL whenever the state is idle, since non-NULL values
aren't expected in that case? This would prevent the weired pg_stat_activity
entries I mentioned earlier, with minimal performance impact.

Regards,

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