Messages in this thread | | | Date | Tue, 1 Jul 2014 11:55:21 +0200 | From | Peter Zijlstra <> | Subject | Re: [RFC PATCH v2] Implement Batched (group) ticket lock |
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On Tue, Jul 01, 2014 at 03:14:09PM +0530, Raghavendra K T wrote: > On 07/01/2014 01:35 PM, Peter Zijlstra wrote: > >On Sat, Jun 28, 2014 at 02:47:04PM +0530, Raghavendra K T wrote: > >>In virtualized environment there are mainly three problems > >>related to spinlocks that affects performance. > >>1. LHP (lock holder preemption) > >>2. Lock Waiter Preemption (LWP) > >>3. Starvation/fairness > >> > >>Though Ticketlocks solve fairness problem it worsens LWP, LHP problems. Though > >>pv-ticketlocks tried to address these problems we can further improve at the > >> cost of relaxed fairness. The following patch tries to achieve that by grouping > >>(batched) ticketlocks. > > > >And here I stop reading and ignore this patch, right? > > > >Why should I look at this? > > > > For baremetal we continue to have 'fully fair ticketlock' with this patch > series. >
But but but, we're looking at removing ticket locks. So why do we want to invest in them now?
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