logo       

RE: GHC-6.4.1 much slower than GHC-6.4: msg#00077

lang.haskell.glasgow.bugs

Subject: RE: GHC-6.4.1 much slower than GHC-6.4

On 28 October 2005 13:12, Mirko Rahn wrote:

>> Can you try with -fno-full-laziness (with both compilers). I wonder
>> if it's a "does this get floated out" issue.
>
> Bit slower than without this flag:
>
> 6.4: cpu-time interesting (3,3): 00:01:40.46
> 6.4.1: cpu-time interesting (3,3): 00:06:11.13
>
> But the ratio keeps the same.

If you can find the root of the computation that is being evaluated
multiple times with 6.4.1, that would help a great deal. The call-tree
on the time profile should help a lot, and you can narrow it down by
inserting {-# SCC #-} annotations. Basically we want to know which
expression is being evaluated multiple times.

Cheers,
Simon


<Prev in Thread] Current Thread [Next in Thread>
Google Custom Search

News | FAQ | advertise