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From: Melanie Plageman <melanieplageman@gmail.com>
Date: Mon, 30 Mar 2026 18:37:27 -0400
Message-ID: 
 <CAAKRu_ZRf_t4=5y5nvq3BKoN8=8Dh77O0pi6s2kScXiAnA3eVQ@mail.gmail.com>
Subject: Re: Don't synchronously wait for already-in-progress IO in read
 stream
To: Alexander Lakhin <exclusion@gmail.com>
Cc: Andres Freund <andres@anarazel.de>,
 Nazir Bilal Yavuz <byavuz81@gmail.com>,
	Thomas Munro <thomas.munro@gmail.com>, pgsql-hackers@postgresql.org,
	Peter Geoghegan <pg@bowt.ie>, Tomas Vondra <tv@fuzzy.cz>
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On Mon, Mar 30, 2026 at 3:14=E2=80=AFPM Melanie Plageman
<melanieplageman@gmail.com> wrote:
>
> On Mon, Mar 30, 2026 at 3:00=E2=80=AFPM Alexander Lakhin <exclusion@gmail=
.com> wrote:
> >
> > As copperhead showed [1], tests added in 020c02bd9 fail when postgres i=
s
> > built without --enable-cassert. I've reproduced the failure locally wit=
h:
>
> Yes, it's because read_buffers() (in test_aio.c) uses
> operation->nblocks and that's only intialized for buffer hits in
> assert builds. The test code could just use the correctly initialized
> nblocks out parameter.

Fix was a little more invasive than that. Looks like we were using
operation in more places than I thought. See attached.

- Melanie

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