From: Greg Stark <gsstark@mit.edu>
To: Mark Lewis <mark.lewis@mir3.com>
Cc: Dan Gorman <dgorman@hi5.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Postgres fsync off (not needed) with NetApp
Date: 14 Jun 2006 23:33:53 -0400
Message-ID: <873be7ay8u.fsf@stark.xeocode.com> (raw)
In-Reply-To: <1150322085.31200.39.camel@archimedes>
References: <9A377C54-361D-4F01-BF7A-7632FBA3453C@hi5.com>
<1150322085.31200.39.camel@archimedes>
Mark Lewis <mark.lewis@mir3.com> writes:
> On Wed, 2006-06-14 at 14:48 -0700, Dan Gorman wrote:
> >
> > However, if I have it attached to a NetApp that ensures data writes
> > to via the NVRAM can I safely turn fsync off to gain additional
> > performance?
>
> No. You need fsync on in order to force the data to get TO the NetApp
> at the right time. With fsync off, the data gets cached in the
> operating system.
In fact the benefit of the NVRAM is precisely that it makes sure you *don't*
have any reason to turn fsync off. It should make the fsync essentially free.
--
greg
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To: pgsql-performance@postgresql.org
Cc: gsstark@mit.edu, mark.lewis@mir3.com, dgorman@hi5.com
Subject: Re: Postgres fsync off (not needed) with NetApp
In-Reply-To: <873be7ay8u.fsf@stark.xeocode.com>
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