Jack, My bus is 1.33 GHz--I think the 2nd Gen Quad-cores are bumped to 1.5 GHz maybe. I'll see if there is anything I can do to bump the numbers. My system is just like yours but with a second Quad core chip that only a few apps can take advantage of. It helps me with Modo, Lightwave, Shake, Photoshop, and Final Cut Studio (which is why I got it in the first place) but not with Python and most other apps as well.
Skip is right of course--the Global Interpreter Lock doesn't play here since the benchmark wasn't written to take advantage of multi-core machines--silly me I thought any good benchmark would be. In the end my error doesn't matter since, if one made the benchmark multi- threaded in the true sense of the term, the GIL would clamp down and limit the benefit anyway. Which is what I was alluding to and should have been more clear about. My point was that, as I understand it, thanks to the GIL--Python cannot easily take advantage of multi-cores period even when the program uses multiple threads--it it is a limitation of the implementation of the language interpreter. I guess that tells us we ought to write multi-core code in C/C++/ObjC instead. Either that or Python's implementation needs to embrace threading more expansively. Still Python is a great language as it is. No one language fits all-- as much as we'd like it to for simplicity's sake. Daniel On Jan 20, 2008, at 11:53 AM, Jack Jansen wrote: > > On 20-Jan-2008, at 19:23 , Daniel Lord wrote: > >> I ran the test on my 1st Gen Quad Core ( 2 x Quad-core 3.0 GHz, 13GB >> RAM) and was a bit surprised to see little improvement over the Core >> Duo numbers. >> >> 63019.7 pystones/second >> >> I am assuming the GIL is limiting threading and therefore I am >> really >> running on one or two cores--hence the tangible improvement is just >> CPU speed: from 2.33 GHz to 3.0 GHz and a bit of the memory bandwidth >> increase as well. > > > Interesting... > My first generation quadcore at 2.6 Ghz clocks at 62578.2. > > So there's another limiting factor: from my machine to yours is a > 15% speed bump, but only a 1% increase in pystone numbers. > > Somebody told me recently that MacOSX is not very good for fast task > switching with multiprocessors, because apparently (his words, and > possibly misrepresented by me) the implementation of semaphores > sucks. This seems to corroborate that. > > Hmm, what is your bus speed? Mine is 1.33 Ghz, is yours that as well > is it 1.5 Ghz? If the former it could be that semaphores somehow run > at bus speed and semaphore overhead dwarves any processing done. If > your bus runs at 1.5Ghz there must be yet another bottleneck... > -- > Jack Jansen, <[EMAIL PROTECTED]>, http://www.cwi.nl/~jack > If I can't dance I don't want to be part of your revolution -- Emma > Goldman > > _______________________________________________ Pythonmac-SIG maillist - Pythonmac-SIG@python.org http://mail.python.org/mailman/listinfo/pythonmac-sig