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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Fujii Masao <masao.fujii@oss.nttdata.com>
cc: Alvaro Herrera <alvherre@2ndquadrant.com>,
        Tomas Vondra <tomas.vondra@2ndquadrant.com>,
        Masahiko Sawada <masahiko.sawada@2ndquadrant.com>,
        "tsunakawa.takay@fujitsu.com" <tsunakawa.takay@fujitsu.com>,
        "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: SLRU statistics
In-reply-to: <ffc93765-84f2-6363-fb3e-4d694c996f37@oss.nttdata.com>
References: <20200513161406.GA437@alvherre.pgsql>
 <ffc93765-84f2-6363-fb3e-4d694c996f37@oss.nttdata.com>
Comments: In-reply-to Fujii Masao <masao.fujii@oss.nttdata.com>
	message dated "Thu, 14 May 2020 01:41:57 +0900"
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Fujii Masao <masao.fujii@oss.nttdata.com> writes:
> But since the counter that postmaster incremented is propagated to
> child processes via fork, it should be zeroed at postmaster or the
> beginning of child process? Otherwise that counter always starts
> with non-zero in child process.

Yes, if the postmaster is incrementing these counts then we would
have to reset them at the start of each child process.  I share
Alvaro's feeling that that's bad and we don't want to do it.

>> (IIRC only the Async module is doing that.)

Hm, maybe we can fix that.

			regards, tom lane