On Tue, Jan 05, 2010 at 04:06:09PM -0800, Mark Lentczner wrote:
In preparing the speed ups in uuid-0.1.2, I investigated various ways to store 16 bytes of data in a Haskell object. Surprisingly, storing as 4 Word32 values in a standard data type worked best for that application.
However, on an Core 2 Duo in x86-64 mode with GHC 6.10, 2 Word64 values wins over 4 Word32 values. Attached is the modified source code. Here is the summary between them equal-itself/words 76.41 ns equal-itself/words64 64.52 ns equal-same/words 79.64 ns equal-same/words64 67.85 ns equal-differ/words 66.11 ns equal-differ/words64 62.79 ns compare-same/words 80.59 ns compare-same/words64 68.68 ns compare-differ/words 67.14 ns compare-differ/words64 64.22 ns toList-and-sum/words 991.32 ns toList-and-sum/words64 839.45 ns map-and-sum/words 1.04 us map-and-sum/words64 1.12 us fold-and-sum/words 882.88 ns fold-and-sum/words64 755.98 ns fromList-and-eq/words 740.41 ns fromList-and-eq/words64 749.07 ns build-and-eq/words 484.54 ns build-and-eq/words64 447.81 ns unfold-and-eq/words 577.12 ns unfold-and-eq/words64 541.46 ns Cheers, -- Felipe.