From owner-freebsd-hackers  Thu Jun 18 17:00:14 1998
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Date: Thu, 18 Jun 1998 19:57:45 -0400 (EDT)
From: Alfred <perlsta@fs2.ny.genx.net>
To: spork <spork@super-g.com>
cc: hackers@FreeBSD.ORG
Subject: Re: Disk Cache
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you could mount "sync", the problem with this is that there will still be
read buffers for cached read data, however you can try it.  in fact it's
kinda good that it will keep buffers available for reading because then
you don't have to hit the interface all that much and do memory to
memory copying or dma requests...

-Alfred

On Thu, 18 Jun 1998, spork wrote:

> Hi,
> 
> I have a question about FBSD's disk cache mechanism.  What happens when
> you run a SCSI-SCSI raid controller that contains it's own cache memory?
> The kernel has no way of knowing that some things are already cached out
> beyond the SCSI card, so I assume it would cache something that's already
> cached, right?  How do you work around that?  Is there some way of telling
> it "hey, don't be very aggressive with your disk caching"?  Or is it such
> a low priority thing that memory isn't used for cache unless there's no
> other use for it?
> 
> Thanks,
> 
> Charles
> 
> Charles Sprickman
> spork@super-g.com
> 
> 
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