To: Craig James <craig_james@emolecules.com>
Cc: PostgreSQL Performance <pgsql-performance@postgresql.org>,
	Matthew Wakeling <matthew@flymine.org>
Subject: Re: select on 22 GB table causes "An I/O error occured while sending
	to the backend." exception
References: <BAY124-W57D3654AF1159CAF8EAC19F5660@phx.gbl>
	<82bpze3ou8.fsf@mid.bfk.de>
	<alpine.DEB.1.10.0808271436210.907@asgard.lang.hm>
	<alpine.DEB.1.10.0808281411220.4454@aragorn.flymine.org>
	<EADBB336-A14E-492C-A8CA-105C8F77A43A@blighty.com>
	<alpine.DEB.1.10.0808281702450.4454@aragorn.flymine.org>
	<48B6EA7E.2090707@emolecules.com> <82d4j5ls9z.fsf@mid.bfk.de>
	<48CE6D0D.80509@emolecules.com>
From: Florian Weimer <fweimer@bfk.de>
Date: Mon, 15 Sep 2008 16:15:38 +0200
In-Reply-To: <48CE6D0D.80509@emolecules.com> (Craig James's message of "Mon,
	15 Sep 2008 07:11:25 -0700")
Message-ID: <82ej3ljy0l.fsf@mid.bfk.de>
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* Craig James:

>> There are some run-time environments which allocate huge chunks of
>> memory on startup, without marking them as not yet in use.  SBCL is in
>> this category, and also the Hotspot VM (at least some extent).
>
> I stand by my assertion: It never makes sense.  Do these
> applications allocate a terrabyte of memory?  I doubt it.

SBCL sizes its allocated memory region based on the total amount of
RAM and swap space.  In this case, buying larger disks does not
help. 8-P

--=20
Florian Weimer                <fweimer@bfk.de>
BFK edv-consulting GmbH       http://www.bfk.de/
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