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Date: Thu, 21 Mar 2024 20:03:32 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-hackers@lists.postgresql.org, alex work <alexwork033@gmail.com>,
	Robert Haas <robertmhaas@gmail.com>
Subject: Re: Slow GRANT ROLE on PostgreSQL 16 with thousands of ROLEs
Message-ID: <20240322010332.GA2109205@nathanxps13>
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On Thu, Mar 21, 2024 at 08:59:54PM -0400, Tom Lane wrote:
> However ... I just remembered that we have a Bloom filter implementation
> in core now (src/backend/lib/bloomfilter.c).  How about using that
> to quickly reject (hopefully) most role OIDs, and only do the
> list_member_oid check if the filter passes?

Seems worth a try.  I've been looking for an excuse to use that...

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