From owner-freebsd-hackers@FreeBSD.ORG  Sun Jun 25 07:41:34 2006
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Cc: freebsd-hackers@freebsd.org
Subject: Re: A New FreeBSD Server
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In message: <20060625064303.GR19592@silverwraith.com>
            Avleen Vig <lists-freebsd@silverwraith.com> writes:
: On Sat, Jun 24, 2006 at 03:32:26PM -0400, Mike Meyer wrote:
: > Why not RAID your swap? The extra reliability might not be worth very
: > much, but the extra performance couldn't hurt - unless you don't plan
: > on swapping at all. This is enough of a win that the swap subsystem
: > will interleave swap usage across multiple drives, a facility that
: > predates RAID. If you just split your swap across multiple drives, you
: > get RAID0 behavior from swap.
: 
: Really? I thought it was possible to interleave multiple swap devices.
: I'm probably wrong, but I thought I remembered seeing 'interleaved'
: somewhere. Maybe my definition of interleaved is differented from
: someone elses :-)

Swapping to multiple devices does tend, on the average, to spread the
load.  But on the average doesn't mean all the time.  When swapping to
a device that's on a RAID, then you get the interleave every single
time.

Warner