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Subject: Re: svn commit: r271946 - in head/sys: dev/oce dev/vmware/vmxnet3
 dev/xen/netfront kern net netinet ofed/drivers/net/mlx4 sys
To: Adrian Chadd <adrian.chadd@gmail.com>
References: <201409220827.s8M8RRHB031526@svn.freebsd.org>
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From: Hans Petter Selasky <hps@selasky.org>
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Date: Tue, 15 Sep 2015 20:34:42 +0200
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Hi Adrian,

On 09/15/15 19:13, Adrian Chadd wrote:
> I know all of this. What I'm asking is different - what about the
> change(s) that broke/fixed the Xen network performance actually caused
> the change in behaviour? I know things are sensitive to how the mbufs
> are broken up - I'd like to see exactly this.

You need to add statistic counters to the network drivers in question, 
how frequently packets are defragged and/or dropped in the TX path to 
figure that out. Can we continue this discussion elsewhere?

--HPS