Cpupools

Hi,

Following patch-series support cpupools in xen:

The physical cpus of a server are grouped in cpu-pools. Each physical CPU is assigned at most to one cpu-pool. Domains are each restricted to a single cpu-pool. Scheduling does not cross cpu-pool boundaries, so each cpu-pool has an own scheduler.

The cpu-pool of the domain Dom0 will be Pool-0, at boot-time we have to create this cpu-pool implicitly.

The creation of a cpu-pool is similar to the creation of a domain. In a first step the attributes of a cpu-pool have to be defined, in the second step the cpu-pool will be activated (started) by assigning the resources (CPUs) and initializing the scheduler. An activated cpu-pool owns at least one physical CPU.

A physical CPU may be removed from an activated cpu-pool. Further CPUs may be assigned to the cpu-pool. The CPU may be assigned to a cpu-pool only if that CPU is free (not assigned to any other activated cpu-pool). The free CPUs are internally managed.

The poolname will be added as an additional parameter to the configfile of a domain. If no poolname is specified the poolname is defaults to Pool-0. At domain start the domain is added to its cpu-pool, which must be activated.

A started domain can be moved to another activated cpu-pool.

A cpu-pool may be deactivated if there is no active domain assigned to it. A cpu-pool is deactivated by removing the resources (CPUs).

A cpu-pool may be deleted if it is deactivated.

The administration of the cpu-pools is done by xm subcommands.

Patch 1/6: hypervisor support of cpupools
Patch 2/6: support in libxc
Patch 3/6: changes in libxen
Patch 4/6: python stuff (xm, xend)
Patch 5/6: xm-test add-ons for cpupools
Patch 6/6: documentation changes

Juergen

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

Juergen Gross writes ("[Xen-devel] [Patch 0/6] Cpupools"):

Would you care to support this in libxl, please ? xl is going to be the toolstack for the future we hope ...

Thanks,
Ian.

Okay, next round will include libxl support.

Juergen

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

What is the advantage and disadvantage of this? What kind of problem is this trying to solve?

Please see the original discussion on xen-devel:
http://lists.xensource.com/archives/html/xen-devel/2008-12/msg00333.html
This should answer most of your questions.

Juergen

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