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From: Peter Geoghegan <pg@bowt.ie>
Date: Sun, 9 Nov 2025 14:51:08 -0500
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 <CAH2-Wz=3_pmjM4=GLG+D2T=4uGm9dSMWbDTNzhHY3=kLoPPhaw@mail.gmail.com>
Subject: Re: Don't synchronously wait for already-in-progress IO in read
 stream
To: Andres Freund <andres@anarazel.de>
Cc: pgsql-hackers@postgresql.org, Tomas Vondra <tv@fuzzy.cz>,
	Thomas Munro <thomas.munro@gmail.com>
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On Thu, Sep 11, 2025 at 5:46=E2=80=AFPM Andres Freund <andres@anarazel.de> =
wrote:
> The problem leading to that is that we are currently synchronously waitin=
g for
> IO on a buffer when AsyncReadBuffers() encounters a buffer already underg=
oing
> IO. If a block is read twice, that means we won't actually have enough IO=
s in
> flight to have good performance. What's worse, currently the wait is not
> attributed to IO wait (since we're waiting in WaitIO, rather than waiting=
 for
> IO).

This patch no longer cleanly applies. Can you post a new version?

Thanks
--=20
Peter Geoghegan