Feedback-ID: ia2694551:Fastmail
Date: Thu, 14 Mar 2024 11:33:30 +0100
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Jelte Fennema-Nio <postgres@jeltef.nl>
Cc: Jacob Champion <jacob.champion@enterprisedb.com>, 
	Tom Lane <tgl@sss.pgh.pa.us>, Denis Laxalde <denis.laxalde@dalibo.com>, 
	vignesh C <vignesh21@gmail.com>, Thomas Munro <thomas.munro@gmail.com>, 
	Greg Stark <stark@mit.edu>, "Gregory Stark (as CFM)" <stark.cfm@gmail.com>, 
	Jelte Fennema <Jelte.Fennema@microsoft.com>, Daniel Gustafsson <daniel@yesql.se>, 
	Peter Eisentraut <peter@eisentraut.org>, Andres Freund <andres@anarazel.de>, 
	Justin Pryzby <pryzby@telsasoft.com>, Robert Haas <robertmhaas@gmail.com>, 
	"pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
Subject: Re: [EXTERNAL] Re: Add non-blocking version of PQcancel
Message-ID: <202403141033.slawmavaxujy@alvherre.pgsql>
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On 2024-Mar-14, Jelte Fennema-Nio wrote:

> On Wed, 13 Mar 2024 at 20:08, Jacob Champion
> <jacob.champion@enterprisedb.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.

Hmm, isn't this basically saying that we're giving up on reliably
canceling queries altogether?  I mean, maybe we'd like to instead fix
the bug about canceling queries in extended query protocol ...
Isn't that something you're worried about?

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/
"World domination is proceeding according to plan"        (Andrew Morton)