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Re: [Xen-users] Does Xen 3.3 support giga bit network in the guest?

To: John Haxby <john.haxby@xxxxxxxxxx>
Subject: Re: [Xen-users] Does Xen 3.3 support giga bit network in the guest?
From: "Fajar A. Nugraha" <fajar@xxxxxxxxx>
Date: Wed, 11 Feb 2009 20:33:23 +0700
Cc: xen-users@xxxxxxxxxxxxxxxxxxx, Abdul Qadeer <qadeer.qadeer@xxxxxxxxx>
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On Wed, Feb 11, 2009 at 5:33 PM, John Haxby <john.haxby@xxxxxxxxxx> wrote:
> The virtual NIC doesn't limit its speed to 100Mb.   It reports that to the
> guest OS because it has to report _something_ but it doesn't throttle back
> to 100Mb.

Have you tested it? Which HVM OS?
My test (with a rather old RHEL4 HVM) seems to indicate that when
ethtool show 100Mbps link speed on emulated Realtek NIC, that's the
actual speed. I only get 62 Mbps with iperf.

Using pv drivers (from RHEL's kmod-xenpv), ethtool doesn't report
ANYTHING in regards to speed, and iperf (on the same HVM domU) got
about 3 Gbps.

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