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To: Craig Ringer <craig@postnewspapers.com.au>
cc: Peter Schuller <peter.schuller@infidyne.com>,
	pgsql-performance@postgresql.org
Subject: Re: Identifying the nature of blocking I/O 
In-reply-to: <48B1FD1A.7040807@postnewspapers.com.au> 
References: <20080822115243.GA10981@hyperion.scode.org>
	<48B1FD1A.7040807@postnewspapers.com.au>
Comments: In-reply-to Craig Ringer <craig@postnewspapers.com.au>
	message dated "Mon, 25 Aug 2008 08:30:18 +0800"
Date: Sun, 24 Aug 2008 21:37:07 -0400
Message-ID: <866.1219628227@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Craig Ringer <craig@postnewspapers.com.au> writes:
> Peter Schuller wrote:
>> But in general, it would be very interesting to see, at any given
>> moment, what PostgreSQL backends are actually blocking on from the
>> perspective of PostgreSQL.

> The recent work on DTrace support for PostgreSQL will probably give you
> the easiest path to useful results. You'll probably need an OpenSolaris
> or (I think) FreeBSD host, though, rather than a Linux host.

<cant-resist>get a mac</cant-resist>

(Mind you, I don't think Apple sells any hardware that would be really
suitable for a big-ass database server.  But for development purposes,
OS X on a recent laptop is a pretty nice unix-at-the-core-plus-eye-candy
environment.)

			regards, tom lane