From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: David Rowley <dgrowleyml@gmail.com>, Peter Geoghegan <pg@bowt.ie>,
        PostgreSQL-development <pgsql-hackers@postgresql.org>,
        Nikita Glukhov <n.gluhov@postgrespro.ru>,
        Andrew Dunstan <andrew@dunslane.net>
Subject: Re: PG 15 (and to a smaller degree 14) regression due to ExprEvalStep
 size
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Fri, 17 Jun 2022 10:33:08 -0400"
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Date: Fri, 17 Jun 2022 10:53:30 -0400
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I wrote:
> Andres Freund <andres@anarazel.de> writes:
>> Or we could add a timeout.c API that specifies the timeout?

> Don't think that will help: it'd be morally equivalent to
> enable_timeout_at(), which also has to do GetCurrentTimestamp().

BTW, if we were willing to drop get_timeout_start_time(), it might
be possible to avoid doing GetCurrentTimestamp() in enable_timeout_at,
in the common case where the specified timestamp is beyond signal_due_at
so that no setitimer call is needed.  But getting the race conditions
right could be tricky.  On the whole this doesn't sound like something
to tackle post-beta.

			regards, tom lane