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Date: Fri, 29 Oct 2010 15:36:18 +0300
From: Andriy Gapon <avg@icyb.net.ua>
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To: Artemiev Igor <ai@kliksys.ru>
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Cc: freebsd-fs@freebsd.org, freebsd-stable@freebsd.org
Subject: Re: 8.1-STABLE: zfs and sendfile: problem still exists
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on 29/10/2010 12:04 Artemiev Igor said the following:
> Yep, this problem exists. You may workaround it via bumping up
> net.inet.tcp.sendspace up to 128k.  zfs sendfile is very ineffective. I have
> made a small investigation via DTrace, it reads MAXBSIZE chunks, but map in vm
> only one page (4K).  I.e. if you have a file with size 512K, sendfile make
> calls freebsd_zfs_read 128 times.

What svn revision of FreeBSD source tree did you test?

-- 
Andriy Gapon