On Sun, 2014-02-23 at 22:55 -0800, Ali Çehreli wrote: […] > On my quad-core Intel I get the following (I have two actual cores, four > hyperthreads): > > 3.14159 took 441[ms] > 3.14159 took 878[ms] > Speedup 1.99093 > -5.80829e+09 took 98[ms] > -5.80829e+09 took 328[ms] > Speedup 3.34694 > > I am not an expect at all but it looks like the first test cannot take > advantage of hyperthreading but the second one can to some degree.
I'm fairly sure I don't agree with this hypothesis. Two cores with hyperthreads generally means a maximum speed up of 2 with optimized native code. So for me the first one looks fine whereas the second one seems to indicate a problem in std.parallelism. -- Russel. ============================================================================= Dr Russel Winder t: +44 20 7585 2200 voip: sip:russel.win...@ekiga.net 41 Buckmaster Road m: +44 7770 465 077 xmpp: rus...@winder.org.uk London SW11 1EN, UK w: www.russel.org.uk skype: russel_winder
