On Wed, 30 Mar 2016 16:11:59 +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 failed to fork easily. > > The problem was fragmentation caused by zram and GPU driver > pages. Their pages cannot be migrated so compaction cannot > work well, either so reclaimer ends up shrinking all of working > set pages. It made system very slow and even to fail to fork > easily. > > Other pain point is that they cannot work with CMA. > Most of CMA memory space could be idle(ie, it could be used > for movable pages unless driver is using) but if driver(i.e., > zram) cannot migrate his page, that memory space could be > wasted. In our product which has big CMA memory, it reclaims > zones too exccessively although there are lots of free space > in CMA so system was very slow easily. > > To solve these problem, this patch try to add facility to > migrate non-lru pages via introducing new friend functions > of migratepage in address_space_operation and new page flags. > > (isolate_page, putback_page) > (PG_movable, PG_isolated) > > For details, please read description in > "mm/compaction: support non-lru movable page migration". OK, I grabbed all these. I wonder about testing coverage during the -next period. How many people are likely to exercise these code paths in a serious way before it all hits mainline? _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
