> Iram reported compaction's too_many_isolated loops forever.
> (
http://www.spinics.net/lists/linux-mm/msg08123.html)
>
> The meminfo of situation happened was inactive anon is zero.
> That's because the system has no memory pressure until then.
> While all anon pages was in active lru, compaction could select
> active lru as well as inactive lru. That's different things
> with vmscan's isolated. So we has been two too_many_isolated.
>
> While compaction can isolated pages in both active and inactive,
> current implementation of too_many_isolated only considers inactive.
> It made Iram's problem.
>
> This patch handles active and inactive with fair.
> That's because we can't expect where from and how many compaction would
> isolated pages.
>
> This patch changes (nr_isolated > nr_inactive) with
> nr_isolated > (nr_active + nr_inactive) / 2.
>
> Cc: Iram Shahzad <iram.shahzad@jp.fujitsu.com>
> Acked-by: Mel Gorman <mel@csn.ul.ie>
> Acked-by: Wu Fengguang <fengguang.wu@intel.com>
> Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
