On Sunday 14 September 2014 12:13:44, Brent Cook wrote: > Results for an old Athlon (hmm, I don't remember it running at 10.8 > Ghz before) > > cpu0: AMD Athlon(tm) 64 X2 Dual Core Processor 6000+, 10823.06 MHz > > forktest 0m19.23s real 0m0.72s user 0m22.46s system > forktest+ 0m16.33s real 0m0.50s user 0m18.22s system > > kernel -j2 3m0.68s real 5m10.95s user 0m41.58s system > kernel -j2+ 3m0.45s real 5m10.14s user 0m41.53s system
On Sunday 14 September 2014 19:16:41, Job Snijders wrote: > The speedup kernel seems to perform slightly better: > > [root@speedup ~]# time ./forktest > > real 0m33.134s > user 0m1.230s > sys 0m53.710s > > [root@5.5stable ~]# time ./forktest > > real 0m37.600s > user 0m1.200s > sys 0m59.530s Thanks to both of you for testing. These results are more in line with my Core i7 and I expected the effect to be larger the large the number of CPUs is. Just my 6-year- old Core2 Duo does not fit in there and gives a much larger speedup. Maybe it is particularily bad at something the current pmap code does.
