From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alexander Lakhin <exclusion@gmail.com>
cc: Pavel Borisov <pashkin.elfe@gmail.com>, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #18616: Long-running hash index build can not be interrupted
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References: <18616-acbb9e5caf41e964@postgresql.org>
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Comments: In-reply-to Alexander Lakhin <exclusion@gmail.com>
	message dated "Fri, 13 Sep 2024 21:00:00 +0300"
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Date: Fri, 13 Sep 2024 15:22:26 -0400
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Alexander Lakhin <exclusion@gmail.com> writes:
> 13.09.2024 17:51, Pavel Borisov wrote:
>> I was unable to reproduce it on my machine with these settings. Tried s=
tatement timeouts 30-120s. Index build appears =

>> to be in interruptible phase on my system.

> Yes, the patch works for me. The query is interrupted as expected.
> But I wonder, why don't you the see same?

I see the same result as Alexander: the query fails to time out
after the expected 90 seconds, and it's looping in _h_indexbuild.

Looking at hashbuild, the effective sort_threshold depends on
NBuffers, so maybe if you have that set to a high enough value
it fails to go into the sort path?  If I use

SET maintenance_work_mem =3D '128MB';

instead of the suggested 1GB, I don't see the problem.

			regards, tom lane