forked from luck/tmp_suning_uos_patched
aa0b7ae063
Currently, the update_tg_load_avg() function attempts to update the tg's load_avg value whenever the load changes even for root_task_group where the load_avg value will never be used. This patch will disable the load_avg update when the given task group is the root_task_group. Running a Java benchmark with noautogroup and a 4.3 kernel on a 16-socket IvyBridge-EX system, the amount of CPU time (as reported by perf) consumed by task_tick_fair() which includes update_tg_load_avg() decreased from 0.71% to 0.22%, a more than 3X reduction. The Max-jOPs results also increased slightly from 983015 to 986449. Signed-off-by: Waiman Long <Waiman.Long@hpe.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Ben Segall <bsegall@google.com> Cc: Douglas Hatch <doug.hatch@hpe.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Scott J Norton <scott.norton@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yuyang Du <yuyang.du@intel.com> Link: http://lkml.kernel.org/r/1449081710-20185-4-git-send-email-Waiman.Long@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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| .. | ||
| auto_group.c | ||
| auto_group.h | ||
| clock.c | ||
| completion.c | ||
| core.c | ||
| cpuacct.c | ||
| cpuacct.h | ||
| cpudeadline.c | ||
| cpudeadline.h | ||
| cpupri.c | ||
| cpupri.h | ||
| cputime.c | ||
| deadline.c | ||
| debug.c | ||
| fair.c | ||
| features.h | ||
| idle_task.c | ||
| idle.c | ||
| loadavg.c | ||
| Makefile | ||
| rt.c | ||
| sched.h | ||
| stats.c | ||
| stats.h | ||
| stop_task.c | ||
| wait.c | ||