From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@novell.com>
Subject: Ping: c/s 20526 (tools: avoid cpu over-commitment if
	numa=on)
Date: Wed, 13 Jan 2010 08:15:08 +0000
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Andre,

I'm afraid this change isn't really correct:

>+                cores_per_node =3D info['nr_cpus'] / info['nr_nodes']
>+                nodes_required =3D (self.info['VCPUs_max'] + cores_per_no=
de - 1) / cores_per_node

Simply using cores_per_node (as calculated here) as a divisor is bound
to cause division-by-zero issues, namely when limiting the number of
CPUs on the Xen command line (maxcpus=3D). I'm not sure though, what
a reasonable solution to this might look like, since cores-per-node is
a meaningless thing in an artificial setup like this, and may also be
meaningless in asymmetric configurations. So perhaps we really need
to iterate over nodes while summing up the number of CPUs they
have until the number of needed vCPU-s was reached.

Jan