diff options
Diffstat (limited to 'kernel/sched')
| -rw-r--r-- | kernel/sched/core.c | 1 | ||||
| -rw-r--r-- | kernel/sched/fair.c | 29 |
2 files changed, 22 insertions, 8 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index fbfc4843063..9d255bc0e27 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1537,6 +1537,7 @@ static void __sched_fork(struct task_struct *p) #ifdef CONFIG_NUMA_BALANCING if (p->mm && atomic_read(&p->mm->mm_users) == 1) { p->mm->numa_next_scan = jiffies; + p->mm->numa_next_reset = jiffies; p->mm->numa_scan_seq = 0; } diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index dd18087fd36..4b577863933 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -784,7 +784,8 @@ update_stats_curr_start(struct cfs_rq *cfs_rq, struct sched_entity *se) * numa task sample period in ms */ unsigned int sysctl_numa_balancing_scan_period_min = 100; -unsigned int sysctl_numa_balancing_scan_period_max = 100*16; +unsigned int sysctl_numa_balancing_scan_period_max = 100*50; +unsigned int sysctl_numa_balancing_scan_period_reset = 100*600; /* Portion of address space to scan in MB */ unsigned int sysctl_numa_balancing_scan_size = 256; @@ -806,20 +807,19 @@ static void task_numa_placement(struct task_struct *p) /* * Got a PROT_NONE fault for a page on @node. */ -void task_numa_fault(int node, int pages) +void task_numa_fault(int node, int pages, bool migrated) { struct task_struct *p = current; /* FIXME: Allocate task-specific structure for placement policy here */ /* - * Assume that as faults occur that pages are getting properly placed - * and fewer NUMA hints are required. Note that this is a big - * assumption, it assumes processes reach a steady steady with no - * further phase changes. + * If pages are properly placed (did not migrate) then scan slower. + * This is reset periodically in case of phase changes */ - p->numa_scan_period = min(sysctl_numa_balancing_scan_period_max, - p->numa_scan_period + jiffies_to_msecs(2)); + if (!migrated) + p->numa_scan_period = min(sysctl_numa_balancing_scan_period_max, + p->numa_scan_period + jiffies_to_msecs(10)); task_numa_placement(p); } @@ -858,6 +858,19 @@ void task_numa_work(struct callback_head *work) return; /* + * Reset the scan period if enough time has gone by. Objective is that + * scanning will be reduced if pages are properly placed. As tasks + * can enter different phases this needs to be re-examined. Lacking + * proper tracking of reference behaviour, this blunt hammer is used. + */ + migrate = mm->numa_next_reset; + if (time_after(now, migrate)) { + p->numa_scan_period = sysctl_numa_balancing_scan_period_min; + next_scan = now + msecs_to_jiffies(sysctl_numa_balancing_scan_period_reset); + xchg(&mm->numa_next_reset, next_scan); + } + + /* * Enforce maximal scan/migration frequency.. */ migrate = mm->numa_next_scan; |