Date: Wed, 8 Apr 2026 16:23:45 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Andres Freund <andres@anarazel.de>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Alexander Lakhin <exclusion@gmail.com>,
	Sami Imseih <samimseih@gmail.com>,
	Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>,
	Robert Treat <rob@xzilla.net>, satyanarlapuram@gmail.com,
	pgsql-hackers <pgsql-hackers@postgresql.org>, tndrwang@gmail.com
Subject: Re: Add pg_stat_autovacuum_priority
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On Wed, Apr 08, 2026 at 04:40:03PM -0400, Andres Freund wrote:
> Note that the whole cached state does automatically get reset at the end of
> the transaction (AtEOXact_PgStat()->pgstat_clear_snapshot()), just like it did
> before the shmem stats stuff.

I see a lot of memory used for the pgStatEntryRefHash table, too (e.g., ~16
MB for 100K tables).  What's interesting is that I cannot reproduce similar
usage with views like pg_stat_all_tables.  If memory was not a concern, I
think the "bool *may_free" idea would be fine.  But assuming it is, we will
probably need to do something more creative.

-- 
nathan