To: "pgsql-performance\@postgresql.org" <pgsql-performance@postgresql.org>
Subject: Re: which ext3 fs type should I use for postgresql
References: <1210846262.16664.41.camel@philippe-desktop>
	<Pine.LNX.4.64.0805151217490.16756@aragorn.flymine.org>
	<482C4F3D.6010808@emolecules.com>
From: Guillaume Cottenceau <gc@mnc.ch>
Date: Thu, 15 May 2008 17:08:16 +0200
In-Reply-To: <482C4F3D.6010808@emolecules.com> (Craig James's message of
 "Thu\,
	15 May 2008 07\:57\:01 -0700")
Message-ID: <87ve1fwqov.fsf@mnc.ch>
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Craig James <craig_james 'at' emolecules.com> writes:

> Matthew Wakeling wrote:
>> Probably of more use are some of the other settings:
>>
>>  -m reserved-blocks-percentage - this reserves a portion of the filesystem
>>     that only root can write to. If root has no need for it, you can kill
>>     this by setting it to zero. The default is for 5% of the disc to be
>>     wasted.
>
> This is not a good idea.  The 5% is NOT reserved for root's
> use, but rather is to prevent severe file fragmentation.  As

Also, IIRC when PG writes data up to a full filesystem,
postmaster won't be able to then restart if the filesystem is
still full (it needs some free disk space for its startup).

Or maybe this has been fixed in recent versions?

-- 
Guillaume Cottenceau