Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-11 Thread Raghavendra K T
On 07/11/2013 04:26 PM, Gleb Natapov wrote: On Thu, Jul 11, 2013 at 04:23:58PM +0530, Raghavendra K T wrote: On 07/11/2013 03:41 PM, Gleb Natapov wrote: On Thu, Jul 11, 2013 at 03:40:38PM +0530, Raghavendra K T wrote: Gleb, Can you elaborate little more on what you have in mind regarding per V

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-11 Thread Gleb Natapov
On Thu, Jul 11, 2013 at 04:23:58PM +0530, Raghavendra K T wrote: > On 07/11/2013 03:41 PM, Gleb Natapov wrote: > >On Thu, Jul 11, 2013 at 03:40:38PM +0530, Raghavendra K T wrote: > >>Gleb, > >>Can you elaborate little more on what you have in mind regarding per > >>VM ple_window. (maint

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-11 Thread Raghavendra K T
On 07/11/2013 03:41 PM, Gleb Natapov wrote: On Thu, Jul 11, 2013 at 03:40:38PM +0530, Raghavendra K T wrote: Gleb, Can you elaborate little more on what you have in mind regarding per VM ple_window. (maintaining part of it as a per vm variable is clear to me), but is it that we have to load th

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-11 Thread Gleb Natapov
On Thu, Jul 11, 2013 at 03:40:38PM +0530, Raghavendra K T wrote: > Gleb, > Can you elaborate little more on what you have in mind regarding per > VM ple_window. (maintaining part of it as a per vm variable is clear > to > me), but is it that we have to load that every time of

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-11 Thread Raghavendra K T
On 07/11/2013 03:18 PM, Gleb Natapov wrote: On Thu, Jul 11, 2013 at 02:43:03PM +0530, Raghavendra K T wrote: On 07/10/2013 04:03 PM, Gleb Natapov wrote: [...] trimmed Yes. you are right. dynamic ple window was an attempt to solve it. Probelm is, reducing the SPIN_THRESHOLD is resulting in exc

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-11 Thread Gleb Natapov
On Thu, Jul 11, 2013 at 02:43:03PM +0530, Raghavendra K T wrote: > On 07/10/2013 04:03 PM, Gleb Natapov wrote: > [...] trimmed > > >>>Yes. you are right. dynamic ple window was an attempt to solve it. > >>> > >>>Probelm is, reducing the SPIN_THRESHOLD is resulting in excess halt > >>>exits in unde

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-11 Thread Raghavendra K T
On 07/10/2013 04:03 PM, Gleb Natapov wrote: [...] trimmed Yes. you are right. dynamic ple window was an attempt to solve it. Probelm is, reducing the SPIN_THRESHOLD is resulting in excess halt exits in under-commits and increasing ple_window may be sometimes counter productive as it affects oth

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Konrad Rzeszutek Wilk
Gleb Natapov wrote: >On Wed, Jul 10, 2013 at 11:03:15AM -0400, Konrad Rzeszutek Wilk wrote: >> On Wed, Jul 10, 2013 at 01:47:17PM +0300, Gleb Natapov wrote: >> > On Wed, Jul 10, 2013 at 12:40:47PM +0200, Peter Zijlstra wrote: >> > > On Wed, Jul 10, 2013 at 01:33:25PM +0300, Gleb Natapov wrote: >>

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Gleb Natapov
On Wed, Jul 10, 2013 at 11:03:15AM -0400, Konrad Rzeszutek Wilk wrote: > On Wed, Jul 10, 2013 at 01:47:17PM +0300, Gleb Natapov wrote: > > On Wed, Jul 10, 2013 at 12:40:47PM +0200, Peter Zijlstra wrote: > > > On Wed, Jul 10, 2013 at 01:33:25PM +0300, Gleb Natapov wrote: > > > > > > Here's an idea,

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Konrad Rzeszutek Wilk
On Wed, Jul 10, 2013 at 01:47:17PM +0300, Gleb Natapov wrote: > On Wed, Jul 10, 2013 at 12:40:47PM +0200, Peter Zijlstra wrote: > > On Wed, Jul 10, 2013 at 01:33:25PM +0300, Gleb Natapov wrote: > > > > Here's an idea, trim the damn email ;-) -- not only directed at gleb. > > > Good idea. > > > >

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Raghavendra K T
On 07/10/2013 05:11 PM, Gleb Natapov wrote: On Wed, Jul 10, 2013 at 04:54:12PM +0530, Raghavendra K T wrote: Ingo, Gleb, From the results perspective, Andrew Theurer, Vinod's test results are pro-pvspinlock. Could you please help me to know what will make it a mergeable candidate?. I need to

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Gleb Natapov
On Wed, Jul 10, 2013 at 04:54:12PM +0530, Raghavendra K T wrote: > >>Ingo, Gleb, > >> > >> From the results perspective, Andrew Theurer, Vinod's test results are > >>pro-pvspinlock. > >>Could you please help me to know what will make it a mergeable > >>candidate?. > >> > >I need to spend more time

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Raghavendra K T
dropping stephen becuase of bounce On 07/10/2013 04:58 PM, Raghavendra K T wrote: On 07/10/2013 04:17 PM, Gleb Natapov wrote: On Wed, Jul 10, 2013 at 12:40:47PM +0200, Peter Zijlstra wrote: On Wed, Jul 10, 2013 at 01:33:25PM +0300, Gleb Natapov wrote: Here's an idea, trim the damn email ;-) -

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Gleb Natapov
On Wed, Jul 10, 2013 at 04:58:29PM +0530, Raghavendra K T wrote: > On 07/10/2013 04:17 PM, Gleb Natapov wrote: > >On Wed, Jul 10, 2013 at 12:40:47PM +0200, Peter Zijlstra wrote: > >>On Wed, Jul 10, 2013 at 01:33:25PM +0300, Gleb Natapov wrote: > >> > >>Here's an idea, trim the damn email ;-) -- not

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Raghavendra K T
On 07/10/2013 04:17 PM, Gleb Natapov wrote: On Wed, Jul 10, 2013 at 12:40:47PM +0200, Peter Zijlstra wrote: On Wed, Jul 10, 2013 at 01:33:25PM +0300, Gleb Natapov wrote: Here's an idea, trim the damn email ;-) -- not only directed at gleb. Good idea. Ingo, Gleb, From the results perspecti

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Raghavendra K T
On 07/10/2013 04:03 PM, Gleb Natapov wrote: On Tue, Jul 09, 2013 at 02:41:30PM +0530, Raghavendra K T wrote: On 06/26/2013 11:24 PM, Raghavendra K T wrote: On 06/26/2013 09:41 PM, Gleb Natapov wrote: On Wed, Jun 26, 2013 at 07:10:21PM +0530, Raghavendra K T wrote: On 06/26/2013 06:22 PM, Gleb

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Gleb Natapov
On Wed, Jul 10, 2013 at 12:40:47PM +0200, Peter Zijlstra wrote: > On Wed, Jul 10, 2013 at 01:33:25PM +0300, Gleb Natapov wrote: > > Here's an idea, trim the damn email ;-) -- not only directed at gleb. > Good idea. > > > Ingo, Gleb, > > > > > > From the results perspective, Andrew Theurer, Vino

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Peter Zijlstra
On Wed, Jul 10, 2013 at 01:33:25PM +0300, Gleb Natapov wrote: Here's an idea, trim the damn email ;-) -- not only directed at gleb. > > Ingo, Gleb, > > > > From the results perspective, Andrew Theurer, Vinod's test results are > > pro-pvspinlock. > > Could you please help me to know what will ma

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-10 Thread Gleb Natapov
On Tue, Jul 09, 2013 at 02:41:30PM +0530, Raghavendra K T wrote: > On 06/26/2013 11:24 PM, Raghavendra K T wrote: > >On 06/26/2013 09:41 PM, Gleb Natapov wrote: > >>On Wed, Jun 26, 2013 at 07:10:21PM +0530, Raghavendra K T wrote: > >>>On 06/26/2013 06:22 PM, Gleb Natapov wrote: > On Wed, Jun 26

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-09 Thread Raghavendra K T
On 06/26/2013 11:24 PM, Raghavendra K T wrote: On 06/26/2013 09:41 PM, Gleb Natapov wrote: On Wed, Jun 26, 2013 at 07:10:21PM +0530, Raghavendra K T wrote: On 06/26/2013 06:22 PM, Gleb Natapov wrote: On Wed, Jun 26, 2013 at 01:37:45PM +0200, Andrew Jones wrote: On Wed, Jun 26, 2013 at 02:15:2

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-07-01 Thread Raghavendra K T
On 06/26/2013 09:26 PM, Andrew Theurer wrote: On Wed, 2013-06-26 at 15:52 +0300, Gleb Natapov wrote: On Wed, Jun 26, 2013 at 01:37:45PM +0200, Andrew Jones wrote: On Wed, Jun 26, 2013 at 02:15:26PM +0530, Raghavendra K T wrote: On 06/25/2013 08:20 PM, Andrew Theurer wrote: On Sun, 2013-06-02

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-26 Thread Raghavendra K T
On 06/26/2013 09:41 PM, Gleb Natapov wrote: On Wed, Jun 26, 2013 at 07:10:21PM +0530, Raghavendra K T wrote: On 06/26/2013 06:22 PM, Gleb Natapov wrote: On Wed, Jun 26, 2013 at 01:37:45PM +0200, Andrew Jones wrote: On Wed, Jun 26, 2013 at 02:15:26PM +0530, Raghavendra K T wrote: On 06/25/2013

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-26 Thread Gleb Natapov
On Wed, Jun 26, 2013 at 07:10:21PM +0530, Raghavendra K T wrote: > On 06/26/2013 06:22 PM, Gleb Natapov wrote: > >On Wed, Jun 26, 2013 at 01:37:45PM +0200, Andrew Jones wrote: > >>On Wed, Jun 26, 2013 at 02:15:26PM +0530, Raghavendra K T wrote: > >>>On 06/25/2013 08:20 PM, Andrew Theurer wrote: > >

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-26 Thread Andrew Theurer
On Wed, 2013-06-26 at 15:52 +0300, Gleb Natapov wrote: > On Wed, Jun 26, 2013 at 01:37:45PM +0200, Andrew Jones wrote: > > On Wed, Jun 26, 2013 at 02:15:26PM +0530, Raghavendra K T wrote: > > > On 06/25/2013 08:20 PM, Andrew Theurer wrote: > > > >On Sun, 2013-06-02 at 00:51 +0530, Raghavendra K T w

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-26 Thread Raghavendra K T
On 06/26/2013 08:09 PM, Chegu Vinod wrote: On 6/26/2013 6:40 AM, Raghavendra K T wrote: On 06/26/2013 06:22 PM, Gleb Natapov wrote: On Wed, Jun 26, 2013 at 01:37:45PM +0200, Andrew Jones wrote: On Wed, Jun 26, 2013 at 02:15:26PM +0530, Raghavendra K T wrote: On 06/25/2013 08:20 PM, Andrew The

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-26 Thread Konrad Rzeszutek Wilk
On Wed, Jun 26, 2013 at 03:52:40PM +0300, Gleb Natapov wrote: > On Wed, Jun 26, 2013 at 01:37:45PM +0200, Andrew Jones wrote: > > On Wed, Jun 26, 2013 at 02:15:26PM +0530, Raghavendra K T wrote: > > > On 06/25/2013 08:20 PM, Andrew Theurer wrote: > > > >On Sun, 2013-06-02 at 00:51 +0530, Raghavendr

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-26 Thread Raghavendra K T
On 06/26/2013 06:22 PM, Gleb Natapov wrote: On Wed, Jun 26, 2013 at 01:37:45PM +0200, Andrew Jones wrote: On Wed, Jun 26, 2013 at 02:15:26PM +0530, Raghavendra K T wrote: On 06/25/2013 08:20 PM, Andrew Theurer wrote: On Sun, 2013-06-02 at 00:51 +0530, Raghavendra K T wrote: This series replac

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-26 Thread Gleb Natapov
On Wed, Jun 26, 2013 at 01:37:45PM +0200, Andrew Jones wrote: > On Wed, Jun 26, 2013 at 02:15:26PM +0530, Raghavendra K T wrote: > > On 06/25/2013 08:20 PM, Andrew Theurer wrote: > > >On Sun, 2013-06-02 at 00:51 +0530, Raghavendra K T wrote: > > >>This series replaces the existing paravirtualized s

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-26 Thread Andrew Jones
On Wed, Jun 26, 2013 at 02:15:26PM +0530, Raghavendra K T wrote: > On 06/25/2013 08:20 PM, Andrew Theurer wrote: > >On Sun, 2013-06-02 at 00:51 +0530, Raghavendra K T wrote: > >>This series replaces the existing paravirtualized spinlock mechanism > >>with a paravirtualized ticketlock mechanism. The

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-26 Thread Raghavendra K T
On 06/25/2013 08:20 PM, Andrew Theurer wrote: On Sun, 2013-06-02 at 00:51 +0530, Raghavendra K T wrote: This series replaces the existing paravirtualized spinlock mechanism with a paravirtualized ticketlock mechanism. The series provides implementation for both Xen and KVM. Changes in V9: - Cha

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-25 Thread Andrew Theurer
On Sun, 2013-06-02 at 00:51 +0530, Raghavendra K T wrote: > This series replaces the existing paravirtualized spinlock mechanism > with a paravirtualized ticketlock mechanism. The series provides > implementation for both Xen and KVM. > > Changes in V9: > - Changed spin_threshold to 32k to avoid e

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-07 Thread Jiannan Ouyang
Raghu, thanks for you input. I'm more than glad to work together with you to make this idea work better. -Jiannan On Thu, Jun 6, 2013 at 11:15 PM, Raghavendra K T wrote: > On 06/03/2013 11:51 AM, Raghavendra K T wrote: >> >> On 06/03/2013 07:10 AM, Raghavendra K T wrote: >>> >>> On 06/02/2013 09

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-07 Thread Andrew Theurer
On Fri, 2013-06-07 at 11:45 +0530, Raghavendra K T wrote: > On 06/03/2013 11:51 AM, Raghavendra K T wrote: > > On 06/03/2013 07:10 AM, Raghavendra K T wrote: > >> On 06/02/2013 09:50 PM, Jiannan Ouyang wrote: > >>> On Sun, Jun 2, 2013 at 1:07 AM, Gleb Natapov wrote: > >>> > High level questio

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-06 Thread Raghavendra K T
On 06/03/2013 11:51 AM, Raghavendra K T wrote: On 06/03/2013 07:10 AM, Raghavendra K T wrote: On 06/02/2013 09:50 PM, Jiannan Ouyang wrote: On Sun, Jun 2, 2013 at 1:07 AM, Gleb Natapov wrote: High level question here. We have a big hope for "Preemptable Ticket Spinlock" patch series by Jiann

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-04 Thread Raghavendra K T
On 06/02/2013 01:44 AM, Andi Kleen wrote: FWIW I use the paravirt spinlock ops for adding lock elision to the spinlocks. This needs to be done at the top level (so the level you're removing) However I don't like the pv mechanism very much and would be fine with using an static key hook in the

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-02 Thread Raghavendra K T
On 06/03/2013 07:10 AM, Raghavendra K T wrote: On 06/02/2013 09:50 PM, Jiannan Ouyang wrote: On Sun, Jun 2, 2013 at 1:07 AM, Gleb Natapov wrote: High level question here. We have a big hope for "Preemptable Ticket Spinlock" patch series by Jiannan Ouyang to solve most, if not all, ticketing s

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-02 Thread Raghavendra K T
On 06/02/2013 09:50 PM, Jiannan Ouyang wrote: On Sun, Jun 2, 2013 at 1:07 AM, Gleb Natapov wrote: High level question here. We have a big hope for "Preemptable Ticket Spinlock" patch series by Jiannan Ouyang to solve most, if not all, ticketing spinlocks in overcommit scenarios problem without

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-02 Thread Jiannan Ouyang
On Sun, Jun 2, 2013 at 1:07 AM, Gleb Natapov wrote: > High level question here. We have a big hope for "Preemptable Ticket > Spinlock" patch series by Jiannan Ouyang to solve most, if not all, > ticketing spinlocks in overcommit scenarios problem without need for PV. > So how this patch series co

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-02 Thread Gleb Natapov
On Sun, Jun 02, 2013 at 12:51:25AM +0530, Raghavendra K T wrote: > > This series replaces the existing paravirtualized spinlock mechanism > with a paravirtualized ticketlock mechanism. The series provides > implementation for both Xen and KVM. > High level question here. We have a big hope for "P

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-01 Thread Andi Kleen
On Sat, Jun 01, 2013 at 01:28:00PM -0700, Jeremy Fitzhardinge wrote: > On 06/01/2013 01:14 PM, Andi Kleen wrote: > > FWIW I use the paravirt spinlock ops for adding lock elision > > to the spinlocks. > > Does lock elision still use the ticketlock algorithm/structure, or are > they different? If t

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-01 Thread Jeremy Fitzhardinge
On 06/01/2013 01:14 PM, Andi Kleen wrote: > FWIW I use the paravirt spinlock ops for adding lock elision > to the spinlocks. Does lock elision still use the ticketlock algorithm/structure, or are they different? If they're still basically ticketlocks, then it seems to me that they're complimentar

Re: [PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-01 Thread Andi Kleen
FWIW I use the paravirt spinlock ops for adding lock elision to the spinlocks. This needs to be done at the top level (so the level you're removing) However I don't like the pv mechanism very much and would be fine with using an static key hook in the main path like I do for all the other lock

[PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-01 Thread Raghavendra K T
This series replaces the existing paravirtualized spinlock mechanism with a paravirtualized ticketlock mechanism. The series provides implementation for both Xen and KVM. Changes in V9: - Changed spin_threshold to 32k to avoid excess halt exits that are causing undercommit degradation (after P

[PATCH RFC V9 0/19] Paravirtualized ticket spinlocks

2013-06-01 Thread Raghavendra K T
This series replaces the existing paravirtualized spinlock mechanism with a paravirtualized ticketlock mechanism. The series provides implementation for both Xen and KVM. Changes in V9: - Changed spin_threshold to 32k to avoid excess halt exits that are causing undercommit degradation (after P