From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tomas.vondra@enterprisedb.com>
cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: sequences vs. synchronous replication
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Comments: In-reply-to Tomas Vondra <tomas.vondra@enterprisedb.com>
	message dated "Sat, 18 Dec 2021 21:45:09 +0100"
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Date: Sat, 18 Dec 2021 16:27:12 -0500
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Tomas Vondra <tomas.vondra@enterprisedb.com> writes:
> Here's a PoC demonstrating this idea. I'm not convinced it's the right 
> way to deal with this - it surely seems more like a duct tape fix than a 
> clean solution. But it does the trick.

I was imagining something a whole lot simpler, like "don't try to
cache unused sequence numbers when wal_level > minimal".  We've
accepted worse performance hits in that operating mode, and it'd
fix a number of user complaints we've seen about weird sequence
behavior on standbys.

			regards, tom lane