Re: [PATCH v6 05/11] pvqspinlock, x86: Allow unfair spinlock in a PV guest

2014-03-18 Thread Paolo Bonzini
Il 17/03/2014 20:05, Konrad Rzeszutek Wilk ha scritto: Measurements were done by Gleb for two guests running 2.6.32 with 16 vcpus each, on a 16-core system. One guest ran with unfair locks, one guest ran with fair locks. Two kernel compilations (time make And when you say fair locks are

Re: [PATCH v6 05/11] pvqspinlock, x86: Allow unfair spinlock in a PV guest

2014-03-18 Thread Paolo Bonzini
Il 17/03/2014 19:54, Peter Zijlstra ha scritto: On Mon, Mar 17, 2014 at 01:44:34PM -0400, Waiman Long wrote: The PV ticketlock code was designed to handle lock holder preemption by redirecting CPU resources in a preempted guest to another guest that can better use it and then return the

Re: [PATCH RFC v6 10/11] pvqspinlock, x86: Enable qspinlock PV support for KVM

2014-03-18 Thread Paolo Bonzini
Il 17/03/2014 18:47, Waiman Long ha scritto: Yeah, what I mean is that the patches that enable paravirtualization should also take care of decreasing the unfair-lock jump label when paravirtualization is enabled. As there are people who don't like unfair lock at all, I prefer to give them the

2014 World Conference on IST - Madeira Island, April 15-17

2014-03-18 Thread ML
= WorldCIST'14 = The 2014 World Conference on Information Systems and Technologies April 15-17, Madeira Island, Portugal http://www.aisti.eu/worldcist14/

Re: [PATCH v6 05/11] pvqspinlock, x86: Allow unfair spinlock in a PV guest

2014-03-18 Thread Waiman Long
On 03/17/2014 02:54 PM, Peter Zijlstra wrote: On Mon, Mar 17, 2014 at 01:44:34PM -0400, Waiman Long wrote: The PV ticketlock code was designed to handle lock holder preemption by redirecting CPU resources in a preempted guest to another guest that can better use it and then return the preempted

Re: [PATCH v6 05/11] pvqspinlock, x86: Allow unfair spinlock in a PV guest

2014-03-18 Thread Waiman Long
On 03/17/2014 03:10 PM, Konrad Rzeszutek Wilk wrote: On Mon, Mar 17, 2014 at 01:44:34PM -0400, Waiman Long wrote: On 03/14/2014 04:30 AM, Peter Zijlstra wrote: On Thu, Mar 13, 2014 at 04:05:19PM -0400, Waiman Long wrote: On 03/13/2014 11:15 AM, Peter Zijlstra wrote: On Wed, Mar 12, 2014 at

Re: [PATCH v6 05/11] pvqspinlock, x86: Allow unfair spinlock in a PV guest

2014-03-18 Thread Waiman Long
On 03/18/2014 04:14 AM, Paolo Bonzini wrote: Il 17/03/2014 20:05, Konrad Rzeszutek Wilk ha scritto: Measurements were done by Gleb for two guests running 2.6.32 with 16 vcpus each, on a 16-core system. One guest ran with unfair locks, one guest ran with fair locks. Two kernel compilations