From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: pvUSB backend performance
Date: Mon, 29 Jun 2015 14:46:26 +0100
Message-ID: <55914C32.6040105@citrix.com>
References: <558A9D2A.2020006@suse.com>
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To: Juergen Gross <jgross@suse.com>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>
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On 24/06/15 13:06, Juergen Gross wrote:
> Hi,
> 
> my qemu integrated pvUSB backend is now running stable enough to do
> some basic performance measurements. I've passed a memory-stick with
> about 90MB of data on it to a pv-domU. Then I read all the data on
> it with tar and looked how long this would take (elapsed time):
> 
> in dom0:                     5.2s
> in domU with kernel backend: 6.1s
> in domU with qemu backend:   8.2s
> 
> So the qemu backend is about 30% slower than the kernel backend. Is
> this acceptable?

Yes?  Maybe? I assume you're adding this backend for a reason, so is it
good enough for your workloads?

IMO, It seems a reasonable trade off to not have a bunch of kernel code.

David