ndmitchell: > Hi > > >> This is using GHC 6.10.2 on Windows XP, 2 processors. Is this a known > >> bug, or should I try and replicate it? (benchmark is fairly big and > >> very dependent on internal things, but I suspect the dramatic > >> performance slowdown is unlikely to be related to these bits). > > > > Yes, what's happening is this: GHC 6.10.2 contains some slightly bogus > > heuristics about when to turn on the parallel GC, and it just so > > happens that 8 processors tips it over the point where the parallel GC > > is enabled for young-generation collections. In 6.10.2 the parallel > > GC really didn't help most of the time, but it has undergone a lot of > > tuning since then, and in the HEAD things are much better (see the > > results from our ICFP submission). > > Fantastic! I'll disable parallel garbage collection (I'm fairly > certain it won't have any effect for this application).
How many cores are you planning to use? ... -- Don _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
