Message-ID: <48CE6D0D.80509@emolecules.com>
Date: Mon, 15 Sep 2008 07:11:25 -0700
From: Craig James <craig_james@emolecules.com>
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To: Florian Weimer <fweimer@bfk.de>,
	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>
In-Reply-To: <82d4j5ls9z.fsf@mid.bfk.de>
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Florian Weimer wrote:
> * Craig James:
>> So it never makes sense to enable overcommitted memory when
>> Postgres, or any server, is running.
> 
> 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.  Buy a terrabyte swap disk and disable overcommitted memory.

Craig