Message-ID: <47012AC5.9040808@agliodbs.com>
Date: Mon, 01 Oct 2007 10:13:41 -0700
From: Josh Berkus <josh@agliodbs.com>
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To: Tom Lane <tgl@sss.pgh.pa.us>
CC: pgsql-hackers@postgreSQL.org, pgsql-novice@postgreSQL.org,
	Mija Lee <mija@scharp.org>
Subject: Re: [HACKERS] PG on NFS may be just a bad idea
References: <25517.1191038302@sss.pgh.pa.us>
In-Reply-To: <25517.1191038302@sss.pgh.pa.us>
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Tom,

> Maybe we need to actively discourage people from running Postgres
> against NFS-mounted data directories.  Shane Kerr's paper cited above
> mentions some other rather scary properties, including O_EXCL file
> creation not really working properly.

Wouldn't you be describing a Linux-specific issue, though?  And possibly 
kernel-specific?

It's hard to reconcile this with the real-world performance of 
PostgreSQL on NFS, which is happening all over the place.  Most notably, 
Joe Conway's 20,000 txn/sec.

I *do* think it's an accurate statement that if you're going to use 
Postgres, or any other OLTP database, on NFS you'd better have access to 
a NAS expert.  But to say that it's a bad idea even if you have expert 
help is probably going to far.

--Josh Berkus