Re: [EXTERNAL] Re: Add non-blocking version of PQcancel

From: Jelte Fennema-Nio <postgres(at)jeltef(dot)nl>
To: Jacob Champion <jacob(dot)champion(at)enterprisedb(dot)com>
Cc: Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Denis Laxalde <denis(dot)laxalde(at)dalibo(dot)com>, vignesh C <vignesh21(at)gmail(dot)com>, Thomas Munro <thomas(dot)munro(at)gmail(dot)com>, Greg Stark <stark(at)mit(dot)edu>, "Gregory Stark (as CFM)" <stark(dot)cfm(at)gmail(dot)com>, Jelte Fennema <Jelte(dot)Fennema(at)microsoft(dot)com>, Daniel Gustafsson <daniel(at)yesql(dot)se>, Peter Eisentraut <peter(at)eisentraut(dot)org>, Andres Freund <andres(at)anarazel(dot)de>, Justin Pryzby <pryzby(at)telsasoft(dot)com>, Robert Haas <robertmhaas(at)gmail(dot)com>, "pgsql-hackers(at)lists(dot)postgresql(dot)org" <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Subject: Re: [EXTERNAL] Re: Add non-blocking version of PQcancel
Date: 2024-03-14 09:51:13
Message-ID: CAGECzQQe9n8LCNzvAK08RzvYepKJMdc=2S0goQSuwD-eCS9wwQ@mail.gmail.com
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On Wed, 13 Mar 2024 at 20:08, Jacob Champion
<jacob(dot)champion(at)enterprisedb(dot)com> wrote:
> I hit this on my machine. With the attached diff I can reproduce
> constantly (including with the most recent test patch); I think the
> cancel must be arriving between the bind/execute steps?

Nice find! Your explanation makes total sense. Attached a patchset
that fixes/works around this issue by using the simple query protocol
in the cancel test.

Attachment Content-Type Size
v38-0001-Use-simple-query-protocol-for-cancel-test.patch application/octet-stream 2.3 KB
v38-0003-Start-using-new-libpq-cancel-APIs.patch application/octet-stream 10.7 KB
v38-0002-Revert-Comment-out-noisy-libpq_pipeline-test.patch application/octet-stream 931 bytes

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