On 9/10/07, Guido van Rossum <[EMAIL PROTECTED]> wrote: > On 9/9/07, Nicholas Bastin <[EMAIL PROTECTED]> wrote: > > On 9/9/07, Guido van Rossum <[EMAIL PROTECTED]> wrote: > > > On 9/9/07, Nicholas Bastin <[EMAIL PROTECTED]> wrote: > > > > I'm not suggesting that Python handle small ints itself and then farm > > > > out large integer computations, I'm suggesting that since we've > > > > already coalesced small ints into 'large' ones, we might want to > > > > review the performance implications of that decision, and possibly > > > > consider that other people have already solved this problem. Clearly > > > > GMP appears to fail on a technical level, but there might be other > > > > options worth investigating. > > > > > > The performance problems that are affecting us most are for > > > small-value ints. The old PyInt type has many custom optimizations to > > > help. I think we could do worse than re-introducing some of the same > > > tricks, retargeted to PyLong (which never got much attention for > > > small-value performance). > > > > I did redo my benchmark using 200 as the increment number instead of > > 1, to duck any impact from the interning of small value ints in 2.6, > > and it made no discernible difference in the results. > > I'm sorry, I've lost context. I'm not at all clear at this point what > benchmark you might have ran.
I posted a tiny snippet of code earlier in the thread that was a sortof silly benchmark of integer math operations. > Note that when I said "small values" I meant (in part) anything that > fits in a Python long -- while there's a special cache in 2.x for ints > < 100, there's also a special allocator that outperforms the obmalloc > allocator. Yeah, my point was mostly an aside to anyone that might have questioned my earlier results of a 2.3x slowdown on integer-sized values because I used 1. A quick switch to 200 netted the exact same results, and a more extensive refactoring to get the same number of operations on a random set of larger numbers netted the same result as well. -- Nick _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
