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From: Hannu Krosing <hannuk@google.com>
Date: Thu, 8 Jun 2023 17:02:08 +0200
Message-ID: <CAMT0RQTCFec0J4hQDcpC0CZ4F-7VWFZXpREgaRU-96bVQ1pj2Q@mail.gmail.com>
Subject: Re: Let's make PostgreSQL multi-threaded
To: Robert Haas <robertmhaas@gmail.com>
Cc: Matthias van de Meent <boekewurm+postgres@gmail.com>, Andres Freund <andres@anarazel.de>, 
	"Jonathan S. Katz" <jkatz@postgresql.org>, Heikki Linnakangas <hlinnaka@iki.fi>, Tom Lane <tgl@sss.pgh.pa.us>, 
	pgsql-hackers <pgsql-hackers@postgresql.org>
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On Thu, Jun 8, 2023 at 4:56=E2=80=AFPM Robert Haas <robertmhaas@gmail.com> =
wrote:
>
> On Thu, Jun 8, 2023 at 8:44=E2=80=AFAM Hannu Krosing <hannuk@google.com> =
wrote:
> > > That sounds like a bad idea, dynamic shared memory is more expensive
> > > to maintain than our static shared memory systems, not in the least
> > > because DSM is not guaranteed to share the same addresses in each
> > > process' address space.
> >
> > Then this too needs to be fixed
>
> Honestly, I'm struggling to respond to this non-sarcastically. I mean,
> I was the one who implemented DSM. Do you think it works the way that
> it works because I considered doing something smart and decided to do
> something dumb instead?

No, I meant that this needs to be fixed at OS level, by being able to
use the same mapping.

We should not shy away from asking the OS people for adding the useful
features still missing.

It was mentioned in the Unconference Kernel Hacker AMA talk and said
kernel hacker works for Oracle, andf they also seemed to be needing
this :)