[Haskell-cafe] Vedr: To my boss: The code is cool, but it is about 100 times slower than the old one...

Daniel Fischer daniel.is.fischer at googlemail.com
Thu Nov 29 22:32:46 CET 2012

On Donnerstag, 29. November 2012, 21:00:36, Fixie Fixie wrote:
> The program seems to take around 6 seconds on my linux-box, while the c
> version goes for 0.06 sekcond.
> That is really some regression bug :-)
> Anyone with a more recent version thatn 7.4.1?

I don't even have a problem with 7.4.1:

$ for ghc in $GHCS; do echo $ghc; time ./hskahan-$ghc > /dev/null; done;

real    0m0.217s
user    0m0.214s
sys     0m0.002s

real    0m0.197s
user    0m0.194s
sys     0m0.002s

real    0m0.187s
user    0m0.187s
sys     0m0.000s

real    0m0.253s
user    0m0.249s
sys     0m0.003s

real    0m0.250s
user    0m0.247s
sys     0m0.002s

real    0m0.224s
user    0m0.221s
sys     0m0.002s

$ time ./ckahan > /dev/null

real    0m0.102s
user    0m0.079s
sys     0m0.022s

We have an unpleasant regression in comparison to 7.2.* and the 7.4.* were 
slower than 7.6.1 is, but it's all okay here (not that it wouldn't be nice to 
have it faster still).

Are you on a 32-bit system?

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