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From: David Rowley <dgrowleyml@gmail.com>
Date: Tue, 9 Jul 2024 14:44:23 +1200
Message-ID: <CAApHDvpy2y-WX_2_E3HTAg8b=gOGzUQBYHxfXzqVwEMhKQTTDQ@mail.gmail.com>
Subject: Re: Parallel Bitmap Heap Scan reports per-worker stats in EXPLAIN ANALYZE
To: Tomas Vondra <tomas.vondra@enterprisedb.com>
Cc: Dilip Kumar <dilipbalaut@gmail.com>, David Geier <geidav.pg@gmail.com>, 
	PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
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On Tue, 9 Jul 2024 at 11:51, David Rowley <dgrowleyml@gmail.com> wrote:
> I think we should consider aligning Parallel Hash
> with the other Parallel node behaviour.

I looked at that and quickly realised that it makes sense that
Parallel Hash does something different here.  All the workers are
contributing to building the same hash table, so they're all going to
show the same set of values, provided they managed to help building
it.

We're able to tell how much each worker helped according to EXPLAIN
(ANALYZE, VERBOSE)'s Worker N: rows=n output.  I don't think there's
anything else not already shown that would be interesting to know per
worker.

David