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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>
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Tomas Vondra <tomas.vondra@enterprisedb.com> writes:
> What do you mean by "not caching unused sequence numbers"? Reducing 
> SEQ_LOG_VALS to 1, i.e. WAL-logging every sequence increment?

Right.

> That'd work, but I wonder how significant the impact will be.

As I said, we've accepted worse in order to have stable replication
behavior.

			regards, tom lane