On Wed, 27 Apr 2016 16:48:13 +0900 Minchan Kim <minchan@xxxxxxxxxx> wrote: > Recently, I got many reports about perfermance degradation in embedded > system(Android mobile phone, webOS TV and so on) and easy fork fail. > > The problem was fragmentation caused by zram and GPU driver mainly. > With memory pressure, their pages were spread out all of pageblock and > it cannot be migrated with current compaction algorithm which supports > only LRU pages. In the end, compaction cannot work well so reclaimer > shrinks all of working set pages. It made system very slow and even to > fail to fork easily which requires order-[2 or 3] allocations. > > Other pain point is that they cannot use CMA memory space so when OOM > kill happens, I can see many free pages in CMA area, which is not > memory efficient. In our product which has big CMA memory, it reclaims > zones too exccessively to allocate GPU and zram page although there are > lots of free space in CMA so system becomes very slow easily. > > To solve these problem, this patch tries to add facility to migrate > non-lru pages via introducing new functions and page flags to help > migration. I'm seeing some rejects here against Mel's changes and our patch bandwidth is getting waaay way ahead of our review bandwidth. So I think I'll loadshed this patchset at this time, sorry. -- 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>