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Re: [Xen-users] How to know the network limits?

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Subject: Re: [Xen-users] How to know the network limits?
From: Jordi Espasa Clofent <jespasac@xxxxxxxxxxxx>
Date: Wed, 05 Aug 2009 12:28:58 +0200
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Fajar A. Nugraha escribió:
On Tue, Aug 4, 2009 at 9:07 PM, Jordi Espasa
Clofent<jespasac@xxxxxxxxxxxx> wrote:
I answer myself:

* the network limit (in interruptions sense) is the physical NIC limit,
because of all the level 2 happens in dom0.

Is it?
Last time I check, transfer between domU <-> dom0 (which is all on
virtual interfaces, involving vif and bridge) on a somewhat old
machine (an old Xeon 3.2 GHz) got me around 1-2 Gbps with 100% CPU
usage. So when you have -- say -- a 10Gbps NIC, the physical NIC is no
longer the limiting factor.

If you make a transfer between domU <-> dom0 you're using level 3 (IP) but also level 2 (LINK LAYER, localhost).
So, _in interruptions sense_ the physical limit is the physical NIC limit.

Feel free to correct me if you think my reasoning is wrong. :)

Jordi Espasa Clofent

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