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Date: Thu, 27 Dec 2007 08:50:09 -0500
From: Bill Moran <wmoran@collaborativefusion.com>
To: Mark Mielke <mark@mark.mielke.cc>
Cc: david@lang.hm, Florian Weimer <fw@deneb.enyo.de>,
	Fernando Hevia <fhevia@ip-tel.com.ar>,
	'pgsql-performance' <pgsql-performance@postgresql.org>
Subject: Re: With 4 disks should I go for RAID 5 or RAID 10
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In response to Mark Mielke <mark@mark.mielke.cc>:

> Bill Moran wrote:
> >
> >> What do you mean "heard of"? Which raid system do you know of that reads 
> >> all drives for RAID 1?
> >>     
> >
> > I'm fairly sure that FreeBSD's GEOM does.  Of course, it couldn't be doing
> > consistency checking at that point.
> >   
> According to this:
> 
> http://www.freebsd.org/cgi/man.cgi?query=gmirror&apropos=0&sektion=8&manpath=FreeBSD+6-current&format=html
> 
> There is a -b (balance) option that seems pretty clear that it does not 
> read from all drives if it does not have to: