From mboxrd@z Thu Jan  1 00:00:00 1970
From: Erik Brakkee <erik@brakkee.org>
Subject: network performance between host and guest...
Date: Fri, 17 Dec 2010 23:29:02 +0100
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Hi,


For a backup of data from a VM to a USB mounted disk I want to 
circumvent the USB 1.1 limitations on the guest and instead copy the 
data over to the host using scp/ssh. I have setup a network using virtio 
and NAT like this:

<interface type='network'>
<mac address='52:54:00:6b:0d:36'/>
<source network='default'/>
<target dev='vnet1'/>
<model type='virtio'/>
<alias name='net1'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
</interface>

When I now create a 1GB file using dd and copy it over from the guest to 
the host, I am seeing a performance between 25-30 MB/s.

My question is if this is normal because I have seen others on the 
internet achieve far greater speeds.

In any case the speeds are comparable to current USB 2.0 speeds but I 
intend on using USB 3.0 so would like to get a little bit more out of it.

What would I use to speed this up a bit futher?

Cheers
   Erik