> Changelog since v3 > o Force enable stats during profiling and latencytop > > Changelog since V2 > o Print stats that are not related to schedstat > o Reintroduce a static inline for update_stats_dequeue > > Changelog since V1 > o Introduce schedstat_enabled and address Ingo's feedback > o More schedstat-only paths eliminated, particularly ttwu_stat > > schedstats is very useful during debugging and performance tuning but it > incurs overhead. As such, even though it can be disabled at build time, > it is often enabled as the information is useful. This patch adds a > kernel command-line and sysctl tunable to enable or disable schedstats on > demand. It is disabled by default as someone who knows they need it can > also learn to enable it when necessary. > > The benefits are workload-dependent but when it gets down to it, the > difference will be whether cache misses are incurred updating the shared > stats or not. These measurements were taken from a 48-core 2-socket machine > with Xeon(R) E5-2670 v3 cpus although they were also tested on a single > socket machine 8-core machine with Intel i7-3770 processors. > > > Signed-off-by: Mel Gorman <[email protected]> > Reviewed-by: Matt Fleming <[email protected]>
Reviewed-by: Srikar Dronamraju <[email protected]> -- Thanks and Regards Srikar Dronamraju
