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Date: Sun, 2 May 2010 14:05:59 -0700 (PDT)
From: Dan Magenheimer <dan.magenheimer@oracle.com>
To: Pavel Machek <pavel@ucw.cz>
Cc: Avi Kivity <avi@redhat.com>, Jeremy Fitzhardinge <jeremy@goop.org>,
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       riel@redhat.com
Subject: RE: Frontswap [PATCH 0/4] (was Transcendent Memory): overview
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> From: Pavel Machek [mailto:pavel@ucw.cz]
> 
> > > So what needs to be said here is 'frontswap is XX times faster than
> > > swap_ops based solution on workload YY'.
> >
> > Are you asking me to demonstrate that swap-to-hypervisor-RAM is
> > faster than swap-to-disk?
> 
> I would like comparison of swap-to-frontswap vs. swap-to-RAMdisk.
> 									Pavel

Well, it's not really apples-to-apples because swap-to-RAMdisk
is copying to a chunk of RAM with a known permanently-fixed size
so it SHOULD be faster than swap-to-hypervisor, and should
*definitely* be faster than swap-to-in-kernel-compressed-RAM
but I suppose it is still an interesting comparison.  I'll
see what I can do, but it will probably be a couple days to
figure out how to measure it (e.g. without accidentally measuring
any swap-to-disk).