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Date: Sat, 2 Aug 2003 12:57:41 -0400 (EDT)
From: Robert Watson <rwatson@freebsd.org>
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To: Andy Farkas <andyf@speednet.com.au>
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Subject: Re: headsup: swap_pager.c
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On Sun, 3 Aug 2003, Andy Farkas wrote:

> One last stupid question...
> 
> > Poul-Henning Kamp wrote:
> > > Another thing is that striping does not belong in the swap_pager in
> > > the first place, we have CCD and similar pieces of code for that.
> 
> So when NSWAPDEV is > 1 the CCD module is auto-loaded? 
> 
> How much RAM does the CCD module use? 

I don't have much expertise in this area of the code, but my reading of
the changes proposed by Poul-Henning is that they don't require the use of
CCD to support multiple swap devices, that simply has to do with the
strategy by which bits of swap is targetted at the devices connected to
the swap subsystem.  I.e., swapon /dev/ad0s1b followed by swapon
/dev/ad1s1b doesn't require you to use CCD.  You only have to use CCD if
you want to reproduce the striping effect.

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Network Associates Laboratories