On Fri, Feb 3, 2017 at 8:29 PM, Michal Hocko <mhocko@xxxxxxxxxx> wrote: > On Fri 03-02-17 10:56:42, vinayak menon wrote: >> On Thu, Feb 2, 2017 at 9:31 PM, Michal Hocko <mhocko@xxxxxxxxxx> wrote: >> > >> > Why would you like to chose and kill a task when the slab reclaim can >> > still make sufficient progres? Are you sure that the slab contribution >> > to the stats makes all the above happening? >> > >> I agree that a task need not be killed if sufficient progress is made >> in reclaiming >> memory say from slab. But here it looks like we have an impact because of just >> increasing the reclaimed without touching the scanned. It could be because of >> disimilar costs or not adding adding cost. I agree that vmpressure is >> only a reasonable >> estimate which does not already include few other costs, but I am not >> sure whether it is ok >> to add another element which further increases that disparity. >> We noticed this problem when moving from 3.18 to 4.4 kernel version. With the >> same workload, the vmpressure events differ between 3.18 and 4.4 causing the >> above mentioned problem. And with this patch on 4.4 we get the same results >> as in 3,18. So the slab contribution to stats is making a difference. > > Please document that in the changelog along with description of the > workload that is affected. Ideally also add some data from /proc/vmstat > so that we can see the reclaim activity. Sure, I will add these to the changelog. Thanks, Vinayak -- 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>
