默认情况下sysctl_sched_wakeup_granularity为1 msec * (1 + ilog(ncpus)),比如4核机器默认值为3ms。 Linux v5.13之前的版本可以通过echo X > /proc/sys/kernel/sched_wakeup_granularity或者sudo sysctl kernel.sched_wakeup_granularity_ns=X进行修改。 Linux v5.13以后参数被移动到了/sys/kernel/debug/sched/*目录下。
默认情况下sysctl_sched_wakeup_granularity为1 msec * (1 + ilog(ncpus)),比如4核机器默认值为3ms。 Linux v5.13之前的版本可以通过echo X > /proc/sys/kernel/sched_wakeup_granularity或者sudo sysctl kernel.sched_wakeup_granularity_ns=X进行修改。
} 【2】wakeup_preempt_entity()函数根据sysctl_sched_wakeup_granularity加权平均值和虚拟虚拟运行时间确定是否触发唤醒任务p抢占当前任务curr,伪代码如下: staticintwakeup_preempt_entity(structsched_entity *curr,structsched_entity *se) {//计算当前任务与被唤醒任务虚拟时间差值s64 gran, vdiff = curr->vrunti...
[PATCH 0/2] sched/fair: Enhance sync wakeup for short duration taskslore.kernel.org/lkml/cover.1719295669.git.yu.c.chen@intel.com/#r false sharing是个一直避不开的问题,在patch中,介绍了false sharing可以通过perf c2c方式,分析出来,实际上这种方式完全不是万能的,为什么这么说呢,首先一个很重要的...
sched: do not wakeup-preempt with SCHED_BATCH tasks do not wakeup-preempt with SCHED_BATCH tasks, their preemption is batched too, driven by the tick. Signed-off-by: Ingo Molnar <[EMAIL PROTECTED]> --- kernel/sched_fair.c | 6 +++++ 1 files changed, 6 insertions(+), 0 deletions...
Keep track if the user-space scheduler is not running for too long (USERSCHED_TIMER_NS) and in that case explicitly wakeup an idle CPU and force the user-space scheduler to run. This allows to automatically recover from potential stall conditions when the BPF <-> user-space scheduling pipel...
> cfs_rq->min_vruntime, based on pre-EEVDF behavior, last seen at: > > af4cf40470c2 sched/fair: Add cfs_rq::avg_vruntime > > If there was no such benefit for woken up tasks. Then the scenario I observed > is just conincidentally worse with EEVDF, which can happen when exch...
reactive c1ock synchronization for wire1ess sensor networks with asynchronous wakeup schedu1ingMost of the existing clock synchronization algorithms for wireless sensor networks can be viewed as proactive clock synchronization since they require nodes to periodically synchronize their clock to a reference ...
+ p->sched_class->task_wake_up(rq, p); +#endif out: task_rq_unlock(rq, &flags); @@ -1748,7 +1751,10 @@ void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags) inc_nr_running(p, rq); } check_preempt_curr(rq, p); - wakeup_balance_rt(rq, p);...