From mboxrd@z Thu Jan  1 00:00:00 1970
From: Juergen Gross <juergen.gross@ts.fujitsu.com>
Subject: RFC: automatic NUMA placement
Date: Thu, 16 Sep 2010 15:38:39 +0200
Message-ID: <4C921DDF.6020809@ts.fujitsu.com>
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Hi,

I just stumbled upon the automatic pinning of vcpus on domain creation in
case of NUMA.
This behaviour is questionable IMO, as it breaks correct handling of
scheduling weights on NUMA machines.
I would suggest to switch this feature off per default and make it a
configuration option of xend. It would make sense, however, to change cpu pool
processor allocation to be NUMA-aware.
Switching NUMA off via boot option would remove NUMA-optimized memory
allocation, which would be sub-optimal :-)

What do you think?


Juergen

-- 
Juergen Gross                 Principal Developer Operating Systems
TSP ES&S SWE OS6                       Telephone: +49 (0) 89 3222 2967
Fujitsu Technology Solutions              e-mail: juergen.gross@ts.fujitsu.com
Domagkstr. 28                           Internet: ts.fujitsu.com
D-80807 Muenchen                 Company details: ts.fujitsu.com/imprint.html