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Date: Fri, 06 Nov 2009 12:53:17 -0700
From: Michael Loftis <mloftis@wgops.com>
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Subject: Re: Performance issues with 8.0 ZFS and sendfile/lighttpd
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--On Monday, November 02, 2009 12:55 PM +0100 Ivan Voras 
<ivoras@freebsd.org> wrote:

> Do you have actual disk IO or is the vast majority of your data served
> from the caches? (actually - the same question to the OP)

That's the problem 64GB of RAM and ZFS doesn't seem to use any cache.  It 
also seems to not be realizing when multiple reads are on the same block 
(same issue sorta) and dispatches the same I/O request.