Hi, On Tue 27-12-16 16:45:03, Minchan Kim wrote: > > Patch 3 splits the swap cache radix tree into 64MB chunks, reducing > > the rate that we have to contende for the radix tree. > > To me, it's rather hacky. I think it might be common problem for page cache > so can we think another generalized way like range_lock? Ccing Jan. I agree on the hackyness of the patch and that page cache would suffer with the same contention (although the files are usually smaller than swap so it would not be that visible I guess). But I don't see how range lock would help here - we need to serialize modifications of the tree structure itself and that is difficult to achieve with the range lock. So what you would need is either a different data structure for tracking swap cache entries or a finer grained locking of the radix tree. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR -- 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>