Date: Thu, 28 Jul 2022 15:26:02 -0700
From: Nathan Bossart <nathandbossart@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: "David G. Johnston" <david.g.johnston@gmail.com>,
	Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
	Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: predefined role(s) for VACUUM and ANALYZE
Message-ID: <20220728222602.GA410772@nathanxps13>
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On Tue, Jul 26, 2022 at 01:54:38PM -0400, Robert Haas wrote:
> I think we're down to 0 remaining now, so it'd be hard to justify
> consuming 2 of 0 remaining bits.

AFAICT there are 2 remaining.  N_ACL_RIGHTS is only 14.

> However, I maintain that the solution
> to this is either (1) change the aclitem representation to get another
> 32 bits or (2) invent a different system for less-commonly used
> permission bits. Checking permissions for SELECT or UPDATE has to be
> really fast, because most queries will need to do that sort of thing.
> If we represented VACUUM or ANALYZE in some other way in the catalogs
> that was more scalable but less efficient, it wouldn't be a big deal
> (although there's the issue of code duplication to consider).

Perhaps we could add something like a relacl_ext column to affected
catalogs with many more than 32 privilege bits.  However, if we actually do
have 2 bits remaining, we wouldn't need to do that work now unless someone
else uses them first.  That being said, it's certainly worth thinking about
the future of this stuff.

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