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help / color / mirror / Atom feedFrom: David Rowley <[email protected]>
To: Tomas Vondra <[email protected]>
Cc: Dilip Kumar <[email protected]>
Cc: David Geier <[email protected]>
Cc: PostgreSQL Developers <[email protected]>
Subject: Re: Parallel Bitmap Heap Scan reports per-worker stats in EXPLAIN ANALYZE
Date: Tue, 9 Jul 2024 14:44:23 +1200
Message-ID: <CAApHDvpy2y-WX_2_E3HTAg8b=gOGzUQBYHxfXzqVwEMhKQTTDQ@mail.gmail.com> (raw)
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On Tue, 9 Jul 2024 at 11:51, David Rowley <[email protected]> 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
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Subject: Re: Parallel Bitmap Heap Scan reports per-worker stats in EXPLAIN ANALYZE
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