This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


[Xen-users] vcpus and cpus, plus cpu affinity = ??

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-users] vcpus and cpus, plus cpu affinity = ??
From: Daniele Palumbo <daniele@xxxxxxxxxxxx>
Date: Thu, 8 Feb 2007 10:46:32 +0100
Delivery-date: Thu, 08 Feb 2007 01:46:30 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: KMail/1.9.4

let's suppose i have something like that:
Name                              ID  VCPU  CPU  State  Time(s)  CPU Affinity
Domain-0                           0     0    0   -b-   24842.7  any cpu
Domain-0                           0     1    1   r--    4306.2  any cpu
Domain-0                           0     2    2   -b-    5171.3  any cpu
Domain-0                           0     3    3   -b-    2013.0  any cpu
trip                              18     0    2   -b-    1189.8  any cpu
uni147                            19     0    0   r--   112415.0  0
uni147                            19     1    1   -b-   35259.4  1

trip have 1 vcpu, cpus blank ("").
uni147 have 2 vcpus, cpus = "0-3" (i have 4 opteron 844).

which is the difference between dom0 and uni147, or better why one have "any 
cpu" and the other have "0" and "1" in cpu affinity?

how xen can decide to allocate to one cpu or another?
is supported something like "if cpu 0 will get full, move vcpu 0 of uni147 to 
cpu 3"?
and for trip?

am i wrong if i consider cpu0 the one that will get most of IO of the HW?
the cpu time of dom0 is affected by the usage of the domU for that real cpu?


Xen-users mailing list