Re: [Intel-gfx] [igt-dev] [PATCH i-g-t 1/2] igt/perf_pmu: Aim for a fixed number of iterations for calibrating accuracy

2018-08-13 Thread Tvrtko Ursulin
On 10/08/2018 14:25, Chris Wilson wrote: Quoting Tvrtko Ursulin (2018-08-09 12:54:41) On 08/08/2018 15:59, Chris Wilson wrote: Our observation is that the systematic error is proportional to the number of iterations we perform; the suspicion is that it directly correlates with the number of s

Re: [Intel-gfx] [igt-dev] [PATCH i-g-t 1/2] igt/perf_pmu: Aim for a fixed number of iterations for calibrating accuracy

2018-08-10 Thread Chris Wilson
Quoting Tvrtko Ursulin (2018-08-09 12:54:41) > > On 08/08/2018 15:59, Chris Wilson wrote: > > Our observation is that the systematic error is proportional to the > > number of iterations we perform; the suspicion is that it directly > > correlates with the number of sleeps. Reduce the number of it

Re: [Intel-gfx] [igt-dev] [PATCH i-g-t 1/2] igt/perf_pmu: Aim for a fixed number of iterations for calibrating accuracy

2018-08-09 Thread Tvrtko Ursulin
On 08/08/2018 15:59, Chris Wilson wrote: Our observation is that the systematic error is proportional to the number of iterations we perform; the suspicion is that it directly correlates with the number of sleeps. Reduce the number of iterations, to try and keep the error in check. Signed-off-b