Messages in this thread | | | Subject | Re: Re: [PATCH] mm/vmstats: add counters for the page frag cache | From | Kyeongdon Kim <> | Date | Mon, 4 Sep 2017 10:35:00 +0900 |
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Thanks for your reply, But I couldn't find "NR_FRAGMENT_PAGES" in linux-next.git .. is that vmstat counter? or others?
As you know, page_frag_alloc() directly calls __alloc_pages_nodemask() function, so that makes too difficult to see memory usage in real time even though we have "/meminfo or /slabinfo.." information. If there was a way already to figure out the memory leakage from page_frag_cache in mainline, I agree your opinion but I think we don't have it now.
If those counters too much in my patch, I can say two values (pgfrag_alloc and pgfrag_free) are enough to guess what will happen and would remove pgfrag_alloc_calls and pgfrag_free_calls.
Thanks, Kyeongdon Kim
On 2017-09-01 오후 6:12, Konstantin Khlebnikov wrote: > IMHO that's too much counters. > Per-node NR_FRAGMENT_PAGES should be enough for guessing what's going on. > Perf probes provides enough features for furhter debugging. > > On 01.09.2017 02:37, Kyeongdon Kim wrote: > > There was a memory leak problem when we did stressful test > > on Android device. > > The root cause of this was from page_frag_cache alloc > > and it was very hard to find out. > > > > We add to count the page frag allocation and free with function call. > > The gap between pgfrag_alloc and pgfrag_free is good to to calculate > > for the amount of page. > > The gap between pgfrag_alloc_calls and pgfrag_free_calls is for > > sub-indicator. > > They can see trends of memory usage during the test. > > Without it, it's difficult to check page frag usage so I believe we > > should add it. > > > > Signed-off-by: Kyeongdon Kim <kyeongdon.kim@lge.com> > > ---
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