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To: FreeBSD FS <freebsd-fs@freebsd.org>, John <jwd@freebsd.org>
References: <20120918010812.GA71005@FreeBSD.org> <op.wktwglik34t2sn@tech304>
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Date: Tue, 18 Sep 2012 07:45:31 -0500
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From: Mark Felder <feld@feld.me>
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Subject: Re: XFS/istgt backed 8TB xfs filesystem configuration?
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On Tue, 18 Sep 2012 07:42:14 -0500, John <jwd@freebsd.org> wrote:

>
> Have you found any blocksizes, cache sizes, etc, that seem optimal?
>

I'm providing iSCSI for XEN and VMWare servers and currently have no  
optimal tunings. ZFS's variable block size seems to handle the load just  
fine, and I have plenty of SSDs doing work for me. Just make sure you have  
carefully calculated the number of Connections and Sessions for istgt --  
your multipath and number of LUNs being shared will affect these numbers.