From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>, sulamul@gmail.com,
        bossartn@amazon.com, pgsql-hackers@postgresql.org
Subject: Re: inefficient loop in StandbyReleaseLockList()
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Thu, 28 Oct 2021 15:14:24 -0700"
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Date: Thu, 28 Oct 2021 18:24:51 -0400
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Andres Freund <andres@anarazel.de> writes:
> Which leads to to wonder whether the better fix would be to switch to de=
leting
> the last element, but still use the while (!empty) style. That should co=
nvert
> the O(n^2) due to 1cff1b9 back to O(n). It might or might not be faster/=
slower
> than using foreach(), but it should be within the same ballpark.

Does it matter what order we're releasing the locks in?

			regards, tom lane