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[Xen-users] dom0 using only a single CPU (networking)

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Subject: [Xen-users] dom0 using only a single CPU (networking)
From: fabi.a169@xxxxxxxxx
Date: Fri, 19 Dec 2008 22:31:54 +0100
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I'm using a server with 10Gbps network interfaces and 4 CPUs, running several domUs. The problem is that in this setup, with high network load, dom0 turns out to be the bottleneck, using only a single CPU which is saturated and 100%. So the network speed is bounded to much less than 10Gbps. How could I make dom0 use more CPUs in parallel ? I checked my VCPU setup; i have 4 VCPUs running assigned to dom0. For other kinds of programms running in dom0 user space, they are used.
Could the problem be that the dom0 kernel uses a single thread for all the network forwarding and so can use only one CPU at a time ?

If you have any idea, thank you for sharing your experience.


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