Date: Wed, 8 Apr 2026 19:57:23 -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 05:59:36PM -0400, Andres Freund wrote:
> On 2026-04-08 16:23:45 -0500, Nathan Bossart wrote:
>> What's interesting is that I cannot reproduce similar usage with views like
>> pg_stat_all_tables.
> 
> Hm? That would be very surprising.  Is it possible you used LIMIT 1 or such?
> The way the pg_stat_all_tables view works it only accesses stats data for
> returned rows (because it does all the stats lookups with individiual columns,
> which also makes it really slow, but avoids having to form datums for not
> returned columns).

*facepalm*

I was using count(*).  If I do something like sum(n_dead_tup), I see much
more memory used by pg_stat_all_tables.  Sorry for the noise.

-- 
nathan