On 23-07-17, 08:54, Joel Fernandes wrote: > Currently the iowait_boost feature in schedutil makes the frequency go to max > on iowait wakeups. This feature was added to handle a case that Peter > described where the throughput of operations involving continuous I/O requests > [1] is reduced due to running at a lower frequency, however the lower > throughput itself causes utilization to be low and hence causing frequency to > be low hence its "stuck". > > Instead of going to max, its also possible to achieve the same effect by > ramping up to max if there are repeated in_iowait wakeups happening. This > patch > is an attempt to do that. We start from a lower frequency (policy->min) > and double the boost for every consecutive iowait update until we reach the > maximum iowait boost frequency (iowait_boost_max). > > I ran a synthetic test (continuous O_DIRECT writes in a loop) on an x86 > machine > with intel_pstate in passive mode using schedutil. In this test the > iowait_boost > value ramped from 800MHz to 4GHz in 60ms. The patch achieves the desired > improved > throughput as the existing behavior. > > [1] https://patchwork.kernel.org/patch/9735885/ > > Cc: Srinivas Pandruvada <srinivas.pandruv...@linux.intel.com> > Cc: Len Brown <l...@kernel.org> > Cc: Rafael J. Wysocki <r...@rjwysocki.net> > Cc: Viresh Kumar <viresh.ku...@linaro.org> > Cc: Ingo Molnar <mi...@redhat.com> > Cc: Peter Zijlstra <pet...@infradead.org> > Suggested-by: Peter Zijlstra <pet...@infradead.org> > Suggested-by: Viresh Kumar <viresh.ku...@linaro.org> > Signed-off-by: Joel Fernandes <joe...@google.com> > --- > kernel/sched/cpufreq_schedutil.c | 38 ++++++++++++++++++++++++++++++++------ > 1 file changed, 32 insertions(+), 6 deletions(-)
You Send V7 [1-2]/2 twice, Are they different ? For both the patches: Acked-by: Viresh Kumar <viresh.ku...@linaro.org> -- viresh
