comparison of execution speed of array types

Ketil Z. Malde ketil@ii.uib.no
20 Jan 2003 15:13:24 +0100


"Zdenek Dvorak" <rakdver@hotmail.com> writes:

>>DiffArray seems to be broken :).  Either that or I'm using it
>>incorrectly.

> I've tried to use DiffArray recently and it is terribly slow.

Just another data point.  I'm fumbling around with Arrays these days
(see my recent post on haskell-cafe) and thought I'd try DiffArray.
After all, I'm building large lists of index/values, and applying (//)
to them.

Now, the docs on how to use DAs aren't all that extensive, but I
replaced the type signatures, and at least the type checker is happy.
However, quickCheck (great tool) just prints a digit and hangs there.
Running the compiled program gave:

    sefirot% !nice
    nice time ./a.out +RTS -p -h -K16M

    Fail: thread blocked indefinitely

    Command exited with non-zero status 1
    1.08user 0.03system 0:01.13elapsed 97%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+0outputs (272major+1756minor)pagefaults 0swaps

I'm probably missing something essential, any idea what it might be?

-kzm
-- 
If I haven't seen further, it is by standing in the footprints of giants