On Mon, Apr 10, 2017 at 12:52:15PM +0200, Markus Trippelsdorf wrote: > > --param ggc-min-heapsize=131072 > > 11264.89user 311.88system 24:18.69elapsed 793%CPU (0avgtext+0avgdata > > 1265352maxresident)k > > --param ggc-min-heapsize=262144 > 10778.52user 336.34system 23:15.71elapsed 796%CPU (0avgtext+0avgdata > 1277468maxresident)k > > > --param ggc-min-heapsize=393216 > > 10655.42user 347.92system 23:01.17elapsed 796%CPU (0avgtext+0avgdata > > 1280476maxresident)k > > > > --param ggc-min-heapsize=524288 > > 10565.33user 352.90system 22:51.33elapsed 796%CPU (0avgtext+0avgdata > > 1506348maxresident)k
So 256MB gets 70% of the speed gain of 512MB, but for only 5% of the cost in RSS. 384MB is an even better tradeoff for this testcase (but smaller is safer). Can the GC not tune itself better? Or, not cost so much in the first place ;-) Segher
