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Subject: Re: 12 disks raid setup
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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 ?