Re: Hmmm... why does pl/pgsql code parallelise so badly when queries parallelise fine? Anyone else seen this?

From: Andres Freund <andres(at)anarazel(dot)de>
To: "Graeme B(dot) Bell" <graeme(dot)bell(at)nibio(dot)no>
Cc: Merlin Moncure <mmoncure(at)gmail(dot)com>, postgres performance list <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Hmmm... why does pl/pgsql code parallelise so badly when queries parallelise fine? Anyone else seen this?
Date: 2015-07-08 11:20:43
Message-ID: 20150708112043.GK10242@alap3.anarazel.de
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On 2015-07-08 11:13:04 +0000, Graeme B. Bell wrote:
> I'm guessing you are maybe pressed for time at the moment because I
> already clearly included this on the last email, as well as the links
> to the alternative benchmarks with the same problem I referred to on
> both of my last emails which are also trivial to drop into pgbench
> (cut/paste).

You realize that you want something here, not Merlin, right?

> e.g. did you see these parts of my previous email
>
> "To clear up the issue I build a little test harness around your comment below."
> "http://github.com/gbb/ppppt"

Well, that requires reviewing the source code of the run script and
such.

I think we shouldn't discuss this on two threads (-performance, -bugs),
that makes it hard to follow. Given Tom's more detailed answer I think
the -bugs thread already contains more pertinent information.

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