On Thu 29-01-15 11:32:43, Christoph Lameter wrote: [...] > Subject: vmstat: Reduce time interval to stat update on idle cpu > > It was noted that the vm stat shepherd runs every 2 seconds and > that the vmstat update is then scheduled 2 seconds in the future. > > This yields an interval of double the time interval which is not > desired. > > Change the shepherd so that it does not delay the vmstat update > on the other cpu. We stil have to use schedule_delayed_work since > we are using a delayed_work_struct but we can set the delay to 0. > > > Signed-off-by: Christoph Lameter <cl@xxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxx> > > Index: linux/mm/vmstat.c > =================================================================== > --- linux.orig/mm/vmstat.c > +++ linux/mm/vmstat.c > @@ -1435,8 +1435,8 @@ static void vmstat_shepherd(struct work_ > if (need_update(cpu) && > cpumask_test_and_clear_cpu(cpu, cpu_stat_off)) > > - schedule_delayed_work_on(cpu, &per_cpu(vmstat_work, cpu), > - __round_jiffies_relative(sysctl_stat_interval, cpu)); > + schedule_delayed_work_on(cpu, > + &per_cpu(vmstat_work, cpu), 0); > > put_online_cpus(); > -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>