On Sat, Oct 05, 2019 at 07:48:45AM +0800, Wei Yang wrote: > On Fri, Oct 04, 2019 at 09:11:20AM -0700, Matthew Wilcox wrote: > >On Sat, Oct 05, 2019 at 12:06:32AM +0800, Wei Yang wrote: > >> After this change, kernel build test reduces 20% anon_vma allocation. > > > >But does it have any effect on elapsed time or peak memory consumption? > > Do the same kernel build test and record time: > > > Origin > > real 2m50.467s > user 17m52.002s > sys 1m51.953s > > real 2m48.662s > user 17m55.464s > sys 1m50.553s > > real 2m51.143s > user 17m59.687s > sys 1m53.600s > > > Patched > > real 2m43.733s > user 17m25.705s > sys 1m41.791s > > real 2m47.146s > user 17m47.451s > sys 1m43.474s > > real 2m45.763s > user 17m38.230s > sys 1m42.102s > > > For time in sys, it reduced 8.5%. That's compelling!
