From mboxrd@z Thu Jan  1 00:00:00 1970
From: Fabian Deutsch <fabian.deutsch@gmx.de>
Subject: Re: Network poblems using virtio and tap.
Date: Sat, 06 Sep 2008 14:04:30 +0200
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	 <200809060940.27765.borntraeger@de.ibm.com>
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To: Christian Borntraeger <borntraeger@de.ibm.com>
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Am Samstag, den 06.09.2008, 09:40 +0200 schrieb Christian Borntraeger:
> Am Montag, 1. September 2008 schrieb Fabian Deutsch:
> > Hey.
> > 
> > I'm observing some network problems when using virtio and a tap if.
> > The trouble is a drop of network troughput from abot 90Mbit/s to
about 
> 90kbit/s,
> > after about 1.7 TB of transferred data.
> > 
> > Setup
> > Host: 
> > - Fedora 8, nearly all updates
> > - Intel(R) Xeon(R) CPU           X3210  @ 2.13GHz
> > - 8GB RAM
> > - 2 Guests
> > 
> > Guest:
> > - Fedora 9 all updates
> > - virtio nic using tap
> > - samba sharing a mountpoint using an iscsi target
> 
> Can you tell us what host kernel and what guest kernel you are using?
The were 
> some changes to tun/tap for virtio lately which could make a
difference.

Host:
Fedora 8 x86_64
2.6.25.14-69.fc8 SMP
kvm-72

Guest:
Fedora 9 i386
2.6.25.11-97.fc9.i686


Greetings
- fabian