On Thursday 13 April 2006 08:55, David F. Place wrote:
On Apr 12, 2006, at 3:30 PM, Daniel McAllansmith wrote:
Averages of user time for three runs on an Athlon64 running 64bit linux:
kern 0.29700 ones32 0.30733 table32 0.37333 table 0.38400
I ran a whole lot more of kern and ones32... kern was consistently faster than ones32. Curious.
Yes, especially curious since the algorithm is taken from AMD's optimization guide for the Athlon and Opteron series. I'm not good enough at reading core syntax to be able to see what GHC is doing with it.
I wonder how this other crazy algorithm I found will work on your 64 bit omputer. It is much slower on my 32 bit PPC powerbook for obvious reasons. If you'd like to try it, I'll include an updated BitTwiddle.hs .
Usage: time ./bits 2000000 3000000 64
Averages of user time of five runs on an Athlon64 running 64bit linux: 64 0.1974 kern 0.2980 ones32 0.3240 table32 0.3754 table 0.3798 64 looks to be a good bit faster. You didn't change anything in the ones32 algorithm did you? The other algorithms are taking roughly what they did last time, but ones32 seems consistently slower now. Daniel