Date: Tue, 20 Sep 2022 16:31:17 -0700
From: Nathan Bossart <nathandbossart@gmail.com>
To: Michael Paquier <michael@paquier.xyz>
Cc: Robert Haas <robertmhaas@gmail.com>, Stephen Frost <sfrost@snowman.net>,
	Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>,
	"David G. Johnston" <david.g.johnston@gmail.com>,
	Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: predefined role(s) for VACUUM and ANALYZE
Message-ID: <20220920233117.GA378596@nathanxps13>
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On Tue, Sep 20, 2022 at 11:05:33AM -0700, Nathan Bossart wrote:
> On Tue, Sep 20, 2022 at 02:45:52PM +0900, Michael Paquier wrote:
>> Any impact for the column sizes of the catalogs holding ACL
>> information?  Just asking while browsing the patch set.
> 
> Since each aclitem requires 16 bytes instead of 12, I assume so.  However,
> in my testing, I hit a "row is too big" error with the same number of
> aclitems in a pg_class row before and after the change.  I might be missing
> something in my patch, or maybe I am misunderstanding how arrays of
> aclitems are stored on disk.

Ah, it looks like relacl is compressed.  The column is marked "extended,"
but pg_class doesn't appear to have a TOAST table, so presumably no
out-of-line storage can be used.  I found a couple of threads about this
[0] [1] [2].

[0] https://postgr.es/m/17245.964897719%40sss.pgh.pa.us
[1] https://postgr.es/m/200309040531.h845ViP05881%40candle.pha.pa.us
[2] https://postgr.es/m/29061.1265327626%40sss.pgh.pa.us

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com