sched/fair: Add cfs bandwidth burst statistics
Two new statistics are introduced to show the internal of burst feature
and explain why burst helps or not.
nr_bursts: number of periods bandwidth burst occurs
burst_time: cumulative wall-time (in nanoseconds) that any cpus has
used above quota in respective periods
Co-developed-by: Shanpei Chen <shanpeic@linux.alibaba.com>
Signed-off-by: Shanpei Chen <shanpeic@linux.alibaba.com>
Co-developed-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Signed-off-by: Huaixin Chang <changhuaixin@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20210830032215.16302-2-changhuaixin@linux.alibaba.com
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index f963c81..ccb604a 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -10406,6 +10406,9 @@ static int cpu_cfs_stat_show(struct seq_file *sf, void *v)
seq_printf(sf, "wait_sum %llu\n", ws);
}
+ seq_printf(sf, "nr_bursts %d\n", cfs_b->nr_burst);
+ seq_printf(sf, "burst_time %llu\n", cfs_b->burst_time);
+
return 0;
}
#endif /* CONFIG_CFS_BANDWIDTH */
@@ -10521,16 +10524,20 @@ static int cpu_extra_stat_show(struct seq_file *sf,
{
struct task_group *tg = css_tg(css);
struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth;
- u64 throttled_usec;
+ u64 throttled_usec, burst_usec;
throttled_usec = cfs_b->throttled_time;
do_div(throttled_usec, NSEC_PER_USEC);
+ burst_usec = cfs_b->burst_time;
+ do_div(burst_usec, NSEC_PER_USEC);
seq_printf(sf, "nr_periods %d\n"
"nr_throttled %d\n"
- "throttled_usec %llu\n",
+ "throttled_usec %llu\n"
+ "nr_bursts %d\n"
+ "burst_usec %llu\n",
cfs_b->nr_periods, cfs_b->nr_throttled,
- throttled_usec);
+ throttled_usec, cfs_b->nr_burst, burst_usec);
}
#endif
return 0;