Hi Lei,
Q1: The pin is needed to lock Dom0 to cores 0 & 1.
Q2: It means 4 vcpus are allocated to Dom0, they can float
between physical cores. VCPUs don’t really line up with cores, you can
assign 8 vcpus on a DomU on a 4 core Dom0 box for example. 8 cpus will
appear in the VM but Xen will try to allocate the request within its 4 physucal
cores. Generally assigning more VPUs than you have physical cores is pointless.
Q3: No SMP for a DOMU will mean the kernel is not SMP aware,
this can save a small amount of overhead and improve scheduling in certain
cases on a single core DOMU. I’m not sure what the affect would be on
Dom0, my guess is it won’t be good.
Rob
From: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
[mailto:xen-users-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of lei yang
Sent: 21 May 2010 04:09
To: Xen Mailing List; xen-devel@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-users] What's the different for
"dom0_max_vcpus=4dom0_vcpus_pin" and "dom0_max_vcpus=4" ?
Hi experts,
Q1:What's the different for "dom0_max_vcpus=4 dom0_vcpus_pin"
and "dom0_max_vcpus=4" ?
which will get better performance
Q2: dom0_max_vcpus=4 means "core0-3 will be just used by dom0" or means
"4 cores(not dedicate cores) will be used by dom0, eg: core2-5 or core3-6?
Q3.what does mean "nosmp" , xen, dom0,domU, will just use one
core????if so, can we specify the use different core. eg: dom0=core2
domU=core3? xen will use just one core?
Thanks
Lei
--
"We learn from failure, not from success!"
