On Wed, Jul 13, 2016 at 11:23:13AM +0900, Minchan Kim wrote: > When I tested vmscale in mmtest in 32bit, I found the benchmark > was slow down 0.5 times. > > base node > 1 global-1 > User 12.98 16.04 > System 147.61 166.42 > Elapsed 26.48 38.08 > > With vmstat, I found IO wait avg is much increased compared to > base. > > The reason was highmem_dirtyable_memory accumulates free pages > and highmem_file_pages from HIGHMEM to MOVABLE zones which was > wrong. With that, dirth_thresh in throtlle_vm_write is always > 0 so that it calls congestion_wait frequently if writeback > starts. > > With this patch, it is much recovered. > > base node fi > 1 global-1 fix > User 12.98 16.04 13.78 > System 147.61 166.42 143.92 > Elapsed 26.48 38.08 29.64 > > Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx> Thanks. I'll pick this up and send a follow-on series to Andrew with this included. -- Mel Gorman SUSE Labs -- 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>