Ian Lynagh wrote: > On Sun, Mar 11, 2007 at 08:18:44PM +0000, Dominic Steinitz wrote: >> I have re-written the sha1 code so that it is (hopefully) easy to see that it >> faithfully implements the algorithm (see >> http://www.itl.nist.gov/fipspubs/fip180-1.htm). Having got rid of the space >> leak, I have been trying to improve performance. >> >> Currently, the haskell code is 2 orders of magnitude slower than the sha1sum >> that ships with my linux. > > I don't know if this is useful to you, but darcs has some SHA1 code that > IIRC is much closer to C's performance. It currently uses darcs' own > FastPackedString library, but porting it to ByteString should be fairly > easy. > > See SHA1.lhs in http://www.abridgegame.org/repos/darcs-unstable > > It might even be able to be made faster still by calling lower-level > functions than {shift,rotate}{L,R} directly.
I ended up deciding to call SHA1 routines out of openssl. For applications where this is possible, it does very well, I got about 2.5 times the speed out of it, compared to ordinary C implementations. But, since harchive spends most of its CPU computing SHA1 hashes (and almost all of the rest in zlib), it is worth a complex binding there. Dave _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
