From ec9e04f0bd62a9475ced14344ff4598ed4f3ed5a Mon Sep 17 00:00:00 2001 From: Tyler Nijmeh Date: Sat, 29 Aug 2020 14:29:11 -0700 Subject: [PATCH] Adjust min task util for boost / coloc Signed-off-by: Tyler Nijmeh --- README.md | 10 ++-------- system/bin/ktweak | 4 +--- 2 files changed, 3 insertions(+), 11 deletions(-) diff --git a/README.md b/README.md index eae5da7..1a796ca 100644 --- a/README.md +++ b/README.md @@ -86,14 +86,8 @@ Set the minimum task scheduling period to 2.5ms. With kernel.sched_latency_ns se Increase the time that a task is considered to be cache hot. According to RedHat, increasing this tunable reduces the number of task migrations. This should reduce time spent balancing tasks and increase per-task performance. See RedHat: https://www.redhat.com/files/summit/session-assets/2018/Performance-analysis-and-tuning-of-Red-Hat-Enterprise-Linux-Part-1.pdf -### kernel.sched_min_task_util_for_boost: 35 -This value effects if tasks should be migrated to a higher performant CPU if it's utilization is above this amount (during sched_boost). Allow tasks to be migrated upwards if the user is triggering a touch boost and the task is above 35% utilization. - -### kernel.sched_min_task_util_for_colocation: 25 -This value is the same as the former, except it occurs only for top-app tasks (which are of greater priority than background tasks). Lower this value a bit to use big clusters more for top-app tasks. - -### kernel.sched_min_task_util_for_boost_colocation: 35 -This is the same as kernel.sched_min_task_util_for_boost for older kernel versions. +### kernel.sched_min_task_util_for_colocation: 35 --> 20 +This value determines when top-app tasks (which are of greater priority than background tasks) can be sched_boosted. Lower this value a bit to use big clusters more for top-app tasks. ### kernel.sched_nr_migrate: 32 --> 128 When migrating tasks between CPUs, allow the scheduler to migrate twice as many as usual. This should increase scheduling latency marginally, but increase the performance of SCHED_OTHER tasks. In testing, `cyclictest` reported a 2 microsecond increase in average latency, an a **decrease** in maximum latency of SCHED_FIFO tasks. diff --git a/system/bin/ktweak b/system/bin/ktweak index 9f1410e..95c895e 100644 --- a/system/bin/ktweak +++ b/system/bin/ktweak @@ -117,9 +117,7 @@ write /proc/sys/kernel/sched_tunable_scaling 0 write /proc/sys/kernel/sched_latency_ns 10000000 write /proc/sys/kernel/sched_min_granularity_ns 2500000 write /proc/sys/kernel/sched_migration_cost_ns 1000000 -write /proc/sys/kernel/sched_min_task_util_for_boost 35 -write /proc/sys/kernel/sched_min_task_util_for_colocation 25 -write /proc/sys/kernel/sched_min_task_util_for_boost_colocation 35 +write /proc/sys/kernel/sched_min_task_util_for_colocation 20 write /proc/sys/kernel/sched_nr_migrate 128 write /proc/sys/kernel/sched_schedstats 0 write /proc/sys/kernel/sched_wakeup_granularity_ns 10000000