Message-ID: <fe82d806915911d823f22bccd20cd174d27a60aa.camel@cybertec.at>
Subject: Re: explain
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Marc Millas <marc.millas@mokadb.com>, 
 "pgsql-general@lists.postgresql.org"
	 <pgsql-general@lists.postgresql.org>
Date: Fri, 25 Apr 2025 08:02:02 +0200
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On Fri, 2025-04-25 at 12:36 +1200, David Rowley wrote:
> On Fri, 25 Apr 2025 at 03:06, Laurenz Albe <laurenz.albe@cybertec.at> wro=
te:
> > On Fri, 2025-04-25 at 01:41 +1200, David Rowley wrote:
> > > The 79.3 seconds is the total time spent doing reads for all parallel
> > > workers. 52.6 seconds is the wall clock time elapsed to execute the
> > > query.
> >=20
> > But wouldn't it read "loops=3D3" or similar then?
>=20
> Only if the Nested Loop was below the Gather / Gather Merge node.

Ah, I see.  The I/O time accrued in a different, lower, parallelized step
of the execution plan.

Yours,
Laurenz Albe