Re: Tid scan increments value of pg_stat_all_tables.seq_scan. (but not seq_tup_read)

From: Kasahara Tatsuhito <kasahara(dot)tatsuhito(at)gmail(dot)com>
To: Fujii Masao <masao(dot)fujii(at)oss(dot)nttdata(dot)com>
Cc: Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com>, Masahiko Sawada <masahiko(dot)sawada(at)2ndquadrant(dot)com>, Andres Freund <andres(at)anarazel(dot)de>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Tid scan increments value of pg_stat_all_tables.seq_scan. (but not seq_tup_read)
Date: 2020-02-07 08:28:43
Message-ID: CAP0=ZVJRAwbn3UdqGPtcONU1xDeeES8KR2kG1JsznSHsFKK-Sg@mail.gmail.com
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Hi,

On Fri, Feb 7, 2020 at 5:02 PM Fujii Masao <masao(dot)fujii(at)oss(dot)nttdata(dot)com> wrote:
> BTW, commit 147e3722f7 causing the issue changed currtid_byreloid()
> and currtid_byrelname() so that they also call table_beginscan().
> I'm not sure what those functions are, but probably we should fix them
> so that table_beginscan_tid() is called instead. Thought?
+1, sorry, I overlooked it.

Both functions are used to check whether a valid tid or not with a
relation name (or oid),
and both perform a tid scan internally.
So, these functions should call table_beginscan_tid().

Perhaps unnecessary, I will attach a patch.

Best regards,
--
Tatsuhito Kasahara
kasahara.tatsuhito _at_ gmail.com

Attachment Content-Type Size
fix_tidscan_issues_v6.patch application/octet-stream 4.5 KB

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