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Re: [Xen-users] Network performance problem

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-users] Network performance problem
From: Fridtjof Busse <fbusse@xxxxxx>
Date: Wed, 19 Dec 2007 06:46:07 +0100
Cc: Ralf Kaestner <Ralf.Kaestner@xxxxxx>
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* Ralf Kaestner <Ralf.Kaestner@xxxxxx>:
> Fridtjof Busse wrote:
> > So I started up tcpdump and I see many Retransmit, Out-of-order,
> > Dup and ICMP "fragmentation needed" packets. As every host on the
> > way between
> Are there TCP checksum errors as well in the network trace?
> Whats the guest OS, Linux or Windows?
> Has the guest enabled any TCP task offloading (if yes try turning it
> off)?

I haven't seen any incorrect checksums so far (doesn't mean there
aren't any). It more looks like the packets get somehow duplicated.
The guests are all linux without any special "optimizations", the only
parameters I touched are proxy_arp and forwarding.
Fridtjof Busse

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