Peter Zijlstra d153b15344 sched/core: Fix wake_affine() performance regression ... Eric reported a sysbench regression against commit: 3fed382b46 ("sched/numa: Implement NUMA node level wake_affine()") Similarly, Rik was looking at the NAS-lu.C benchmark, which regressed against his v3.10 enterprise kernel. PRE (current tip/master): ivb-ep sysbench: 2: [30 secs] transactions: 64110 (2136.94 per sec.) 5: [30 secs] transactions: 143644 (4787.99 per sec.) 10: [30 secs] transactions: 274298 (9142.93 per sec.) 20: [30 secs] transactions: 418683 (13955.45 per sec.) 40: [30 secs] transactions: 320731 (10690.15 per sec.) 80: [30 secs] transactions: 355096 (11834.28 per sec.) hsw-ex NAS: OMP_PROC_BIND/lu.C.x_threads_144_run_1.log: Time in seconds = 18.01 OMP_PROC_BIND/lu.C.x_threads_144_run_2.log: Time in seconds = 17.89 OMP_PROC_BIND/lu.C.x_threads_144_run_3.log: Time in seconds = 17.93 lu.C.x_threads_144_run_1.log: Time in seconds = 434.68 lu.C.x_threads_144_run_2.log: Time in seconds = 405.36 lu.C.x_threads_144_run_3.log: Time in seconds = 433.83 POST (+patch): ivb-ep sysbench: 2: [30 secs] transactions: 64494 (2149.75 per sec.) 5: [30 secs] transactions: 145114 (4836.99 per sec.) 10: [30 secs] transactions: 278311 (9276.69 per sec.) 20: [30 secs] transactions: 437169 (14571.60 per sec.) 40: [30 secs] transactions: 669837 (22326.73 per sec.) 80: [30 secs] transactions: 631739 (21055.88 per sec.) hsw-ex NAS: lu.C.x_threads_144_run_1.log: Time in seconds = 23.36 lu.C.x_threads_144_run_2.log: Time in seconds = 22.96 lu.C.x_threads_144_run_3.log: Time in seconds = 22.52 This patch takes out all the shiny wake_affine() stuff and goes back to utter basics. Between the two CPUs involved with the wakeup (the CPU doing the wakeup and the CPU we ran on previously) pick the CPU we can run on _now_. This restores much of the regressions against the older kernels, but leaves some ground in the overloaded case. The default-enabled WA_WEIGHT (which will be introduced in the next patch) is an attempt to address the overloaded situation. Reported-by: Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Rosato <mjrosato@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: jinpuwang@gmail.com Cc: vcaputo@pengaru.com Fixes: 3fed382b46 ("sched/numa: Implement NUMA node level wake_affine()") Signed-off-by: Ingo Molnar <mingo@kernel.org>		2017-10-10 10:14:02 +02:00
..
autogroup.h
clock.h
coredump.h	mm: make PR_SET_THP_DISABLE immediately active	2017-07-10 16:32:31 -07:00
cpufreq.h
cputime.h
deadline.h
debug.h	sched/debug: Use task_pid_nr_ns in /proc/$pid/sched	2017-08-10 12:18:19 +02:00
hotplug.h
idle.h
init.h
jobctl.h
loadavg.h
mm.h	android: binder: drop lru lock in isolate callback	2017-10-03 17:54:24 -07:00
nohz.h
numa_balancing.h
prio.h
rt.h
signal.h
stat.h
sysctl.h
task_stack.h
task.h	sched/core: Remove unnecessary initialization init_idle_bootup_task()	2017-08-10 12:18:18 +02:00
topology.h	sched/core: Fix wake_affine() performance regression	2017-10-10 10:14:02 +02:00
user.h	sock: ulimit on MSG_ZEROCOPY pages	2017-08-03 21:37:30 -07:00
wake_q.h
xacct.h