On Thu 16-03-17 16:56:34, Avi Kivity wrote: > On 03/16/2017 04:48 PM, Michal Hocko wrote: > >On Thu 16-03-17 15:26:54, Avi Kivity wrote: [...] > >>>What is the THP defrag mode > >>>(/sys/kernel/mm/transparent_hugepage/defrag)? > >>The default (always). > >the default has changed since then because the THP faul latencies were > >just too large. Currently we only allow madvised VMAs to go stall and > >even then we try hard to back off sooner rather than later. See > >444eb2a449ef ("mm: thp: set THP defrag by default to madvise and add a > >stall-free defrag option") merged in 4.4 > > I see, thanks. So the 4.4 behavior is better mostly due to not trying so > hard. Please note there were many other patches in the compaction code as well. -- Michal Hocko 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>