From: hubert depesz lubaczewski <depesz@depesz.com>
To: Masahiko Sawada <sawada.mshk@gmail.com>
Cc: PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Subject: Re: I/O timigns don't include time for temp buffers
Date: Wed, 11 Aug 2021 10:35:40 +0200
Message-ID: <20210811083540.GA24169@depesz.com> (raw)
In-Reply-To: <CAD21AoAXPreHPzpkWgOVmRkhipdxkCVVXpndMg84=nTzB=QnZg@mail.gmail.com>
References: <20210709084355.GA6251@depesz.com>
<CAD21AoAXPreHPzpkWgOVmRkhipdxkCVVXpndMg84=nTzB=QnZg@mail.gmail.com>
On Tue, Aug 10, 2021 at 03:15:27PM +0900, Masahiko Sawada wrote:
> > This shows that the Hash wrote 1100 temp buffers, but I/O timings didn't increase at all.
> Yes, we don't collect the time spent reading and writing temp files.
And this is the source of my concern.
Not that we have this documented in one way or another, but why exactly
aren't we taking temp buffers into timing? There are cases where it is
the temp buffers IO that is using most of the time.
Best regards,
depesz
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-bugs@postgresql.org
Cc: depesz@depesz.com, sawada.mshk@gmail.com, pgsql-bugs@lists.postgresql.org
Subject: Re: I/O timigns don't include time for temp buffers
In-Reply-To: <20210811083540.GA24169@depesz.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox