Hello, Kame.

On Tue, Aug 25, 2015 at 11:36:25AM +0900, Kamezawa Hiroyuki wrote:

I think I should explain my customer's use case of qemu + cpuset/cpu (via libvirt)

(1) Isolating hypervisor thread.
   As already discussed, hypervisor threads are isolated by cpuset. But their purpose
   is to avoid _latency_ spike caused by hypervisor behavior. So, "nice" cannot be solution
   as already discussed.

(2) Fixed rate vcpu service.
   With using cpu controller's quota/period feature, my customer creates  vcpu models like
   Low(1GHz), Mid(2GHz), High(3GHz) for IaaS system.

   To do this, each vcpus should be quota-limited independently, with per-thread cpu control.

Especially, the method (1) is used in several enterprise customers for stabilizing their system.

Sub-process control should be provided by some way.

Can you please take a look at the proposal on my reply to Paul's
email?  AFAICS, both of above cases should be fine with that.

Thanks.

-- 
tejun