Messages in this thread | | | Subject | Re: [PATCH 3/3] mm: oom: show unreclaimable slab info when unreclaimable slabs > user memory | From | "Yang Shi" <> | Date | Fri, 20 Oct 2017 07:12:56 +0800 |
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On 10/19/17 12:28 AM, Michal Hocko wrote: > On Tue 17-10-17 15:39:08, David Rientjes wrote: >> On Wed, 18 Oct 2017, Yang Shi wrote: >> >>>> Yes, this should catch occurrences of "huge unreclaimable slabs", right? >>> >>> Yes, it sounds so. Although single "huge" unreclaimable slab might not result >>> in excessive slabs use in a whole, but this would help to filter out "small" >>> unreclaimable slab. >>> >> >> Keep in mind this is regardless of SLAB_RECLAIM_ACCOUNT: your patch has >> value beyond only unreclaimable slab, it can also be used to show >> instances where the oom killer was invoked without properly reclaiming >> slab. If the total footprint of a slab cache exceeds 5%, I think a line >> should be emitted unconditionally to the kernel log. > > agreed. I am not sure 5% is the greatest fit but we can tune that later.
5% might be too few. For example, on a machine with 200G memory, if there is 80G page cache, radix_tree_node might consume 10G. IMHO, 10% might be better.
Yang
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