[Xen-users] Re: how to congure dom0 to 1G, and domU to 1G

[lei yang <yanglei.fage@xxxxxxxxx>]

On Sat, May 22, 2010 at 12:01 AM, Pasi Kärkkäinen <pasik@xxxxxx> wrote:

On Fri, May 21, 2010 at 11:43:48PM +0800, lei yang wrote:
>    On Fri, May 21, 2010 at 8:08 PM, Pasi Kärkkäinen <[1]pasik@xxxxxx> wrote:
>
>      On Thu, May 20, 2010 at 04:59:00PM +0800, lei yang wrote:
>      >    On Thu, May 20, 2010 at 2:04 PM, Pasi Kärkkäinen

>      <[1][2]pasik@xxxxxx> wrote:
>      >
>      >      On Thu, May 20, 2010 at 01:59:16PM +0800, lei yang wrote:
>      >      >    Hi Experts,
>      >      >
>      >
>      >      I removed xen-devel from CC since this is a very basic question,
>      >      and not related to Xen development.
>      >      >    I want to configure dom0 to 1g and dom0 to 1g ?
>      >      >
>      >      >    I know dom0_mem=1024M can do it for dom0, how about domU?
>      >      >
>      >
>      >      Uhm.. for domU you specify:
>      >
>      >      memory = 1024
>      >
>      >      in the domU configuration file (/etc/xen/<guest>).
>      >      >    My machine has 8 cores
>      >      >    how to  specify xen to 4 cpus?
>      >      >
>      >
>      >      Xen is the *hypervisor*, so it has to use ALL the physical
>      CPUs/cores,
>      >      to be able to schedule vcpus!!
>      >
>      >    Do you mean we can't specify xen to 4 cpus, and if we specify
>      "nosmp" what
>      >    does it mean
>      >    it will use *just* one physical core to schedule vcpus? and dom0
>      and domU
>      >    just can use one core?
>      >
>
>      Depends where you specify "nosmp", for Xen or for dom0 kernel.
>
>
>    if I specify to nosmp to "xen", will dom0 and domU just run core one core?
>

I think so. Why would you want to limit everything to just one core ?

 

 

I want to test the xen UP mode performance. so I need to run everything just on one core. if I specify xen to "nosmp"

dom0 and domU will just run on one core, how about xen? just run on one core?

 

Thanks

Lei

 

 

>    can we now which core?
>

I don't think so.

-- Pasi

>
>      Xen *has* to have access to all the physical cpus/cores you want to use
>      for your guest, including dom0.
>
>      See Xen vcpu pinning for more information.
>      >
>      >
>      >      >    how to specify dom0 4 cpus
>      >      >
>      >
>      >      dom0_max_vcpus=4 for xen.gz in grub.conf.
>      >
>      >
>      >
>      >   Specified options "dom0_max_vcpus=2" and "dom0_vcpus_pin".
>      >   Specified option "dom0_max_vcpus=2".
>      >
>      >  what's the difference? which performance will be higher?
>      >
>
>      Adding dom0_vcpus_pin will automatically pin the dom0 vcpus to matching
>      physical cpus.
>      That might not make a difference alone.. you need/want to pin the other
>      guest vcpus aswell,
>      depending what kind of configuration you want to get.
>
>
>    "dom0_max_vcpus=2" and "dom0_vcpus_pin".  core0 and core 1 will just used
>    by  dom0? can't be used by others eg: domU?
>
>      -- Pasi
>
>      >
>      >  Thanks
>      >  Lei
>      >
>      >      >    how to specify domU 5 cpus ?
>      >      >
>      >
>      >      vcpus = 5
>      >      >    can we specify dom0 to 1 cpu, at same time domU to 6 cpu
>      >      >
>      >
>      >      dom0_max_vcpus=1 dom0_vcpus_pin
>      >
>      >      in grub.conf for xen.gz.
>      >      >    can we specify nosmp to xen, and then specify dom0 cpu > 1?
>      >      >
>      >
>      >      No.
>      >

>      >      See: [2][3]http://wiki.xensource.com/xenwiki/XenBestPractices
>      >      and: [3][4]http://wiki.xensource.com/xenwiki/XenCommonProblems

>      >      -- Pasi
>      >      >
>      >      >
>      >      >    Thanks
>      >      >    Lei
>      >      >
>      >      >    --
>      >      >    "We learn from failure, not from success!"
>      >
>      >    --
>      >    "We learn from failure, not from success!"
>      >
>      > References
>      >
>      >    Visible links

>      >    1. mailto:[5]pasik@xxxxxx
>      >    2. [6]http://wiki.xensource.com/xenwiki/XenBestPractices
>      >    3. [7]http://wiki.xensource.com/xenwiki/XenCommonProblems

>
>    --
>    "We learn from failure, not from success!"
>

> References
>
>    Visible links
>    1. mailto:pasik@xxxxxx

>    2. mailto:pasik@xxxxxx
>    3. http://wiki.xensource.com/xenwiki/XenBestPractices
>    4. http://wiki.xensource.com/xenwiki/XenCommonProblems
>    5. mailto:pasik@xxxxxx
>    6. http://wiki.xensource.com/xenwiki/XenBestPractices
>    7. http://wiki.xensource.com/xenwiki/XenCommonProblems

-- 
"We learn from failure, not from success!"
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users