From: Franck Routier <franck.routier@axege.com>
To: pgsql-performance <pgsql-performance@postgresql.org>
Subject: Re: 12 disks raid setup
Date: Sat, 01 Mar 2008 11:27:57 +0100
Message-ID: <1204367277.9116.16.camel@franck-gusty> (raw)
In-Reply-To: <Pine.GSO.4.64.0802292347250.145@westnet.com>
References: <1204285894.11773.33.camel@franck-gusty>
<dcc563d10802290613v482f52dr43ea95b52886de31@mail.gmail.com>
<1204296705.11773.51.camel@franck-gusty>
<Pine.GSO.4.64.0802291019570.28452@westnet.com>
<47C8A6D9.1050502@Sheeky.Biz>
<Pine.GSO.4.64.0802292347250.145@westnet.com>
Hi,
Le vendredi 29 février 2008 à 23:56 -0500, Greg Smith a écrit :
> Wording is intentional--if you don't have a battery for it, the cache has
> to be turned off (or set to write-through so it's only being used on
> reads) in order for the database to be reliable. If you can't finish
> writes after a power off, you can't cache writes and expect your database
> to survive for too long.
Well, am I just wrong, or the file system might also heavily rely on
cache, especially as I use XFS ?
So anyway Postgresql has no way to know if the data is really on the
disk, and in case of a brutal outage, the system may definitely lose
data, wether there is another level of caching (Raid controller) or
not...
Right ?
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To: pgsql-performance@postgresql.org
Cc: franck.routier@axege.com
Subject: Re: 12 disks raid setup
In-Reply-To: <1204367277.9116.16.camel@franck-gusty>
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