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Date: Fri, 29 Aug 2008 16:22:18 +0000 (GMT)
From: Valentin Bogdanov <valiouk@yahoo.co.uk>
Reply-To: valiouk@yahoo.co.uk
Subject: Re: select on 22 GB table causes "An I/O error occured while sending
	to the backend." exception
To: pgsql-performance@postgresql.org
In-Reply-To: <alpine.DEB.1.10.0808291653060.4454@aragorn.flymine.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
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Message-ID: <874031.98985.qm@web25806.mail.ukl.yahoo.com>

In 2003 I met this guy who was doing Computation Fluid Dynamics and he had =
to use this software written by physics engineers in FORTRAN. 1 Gig of ram =
wasn't yet the standard for a desktop pc at that time but the software requ=
ired at least 1 Gig just to get started. So I thought what is the problem a=
fter all you are supposed to be able to allocate upto 2G on a 32 bit system=
 even if you don't quite have the memory and you have sufficiently big swat=
 space. Still, the software didn't load on Windows. So, it seems that Windo=
ws does not overcommit.

regards


--- On Fri, 29/8/08, Matthew Wakeling <matthew@flymine.org> wrote:

> From: Matthew Wakeling <matthew@flymine.org>
> Subject: Re: [PERFORM] select on 22 GB table causes "An I/O error occured=
 while sending to the backend." exception
> To: pgsql-performance@postgresql.org
> Date: Friday, 29 August, 2008, 4:56 PM
> On Fri, 29 Aug 2008, Craig James wrote:
> > Disable overcommitted memory.  There is NO REASON to
> use it on any modern=20
> > server-class computer, and MANY REASONS WHY IT IS A
> BAD IDEA.
>=20
> As far as I can see, the main reason nowadays for
> overcommit is when a=20
> large process forks and then execs. Are there any other
> modern programs=20
> that allocate lots of RAM and never use it?
>=20
> Matthew
>=20
> --=20
> Nog:     Look! They've made me into an ensign!
> O'Brien: I didn't know things were going so badly.
> Nog:     Frightening, isn't it?
>=20
> --=20
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