RE: Performance week 25/6-29/6

On 25 July 2005 10:07, Ketil Malde wrote:

"Simon Marlow" writes:

...

We're interested in performance issues with both GHC itself and GHC-compiled code.

I can think of a couple of things.

One is the performance of Int64 (which unsurprisingly is inferior to Int(32) but more surprisingly, also to Integer). I've reported it previously, but can dig it up again, if desired.

Added to the list, thanks.

The other is probably not as relevant, but I'll mention it anyway. I occasionally use rather large arrays, and UArrays can save a considerable amount of space. Sometimes, however, I want to store more complex structures than those UArrays are provided for. It seems to me that what I really want are *strict* arrays (which the compiler then can unbox automatically), and that these could be provided for any (single constructor) data type?

Manuel Chakravarty's flattened arrays are what you want; I'm not sure of the implementation status though. Also, once we have associated types it will be easier to do this (see the associated types paper for an example). Cheers, Simon