Re: [Haskell-cafe] OCaml list sees abysmal Language Shootout results

Keith Wansbrough wrote:

I just saw this on the OCaml list (in a posting by "Rafael 'Dido' Sevilla" in the "Observations on OCaml vs. Haskell" thread). I can't believe that a simple "wc" implementation should be 570 times slower in Haskell than OCaml - could someone investigate and fix the test?

I've been looking at the other shootout results (with the hope of learning something about making haskell programs faster/less memory hungry) and I couldn't quite figure out why the "Hashes, part II" test comsumes so much memory ( http://shootout.alioth.debian.org/bench/hash2/ ). So I started to try heap profiling, and generated the following graphs for the different types of profiles... biography => http://sleepingsquirrel.org/haskell/hash2_b.ps retainer => http://sleepingsquirrel.org/haskell/hash2_r.ps closure => http://sleepingsquirrel.org/haskell/hash2_d.ps type => http://sleepingsquirrel.org/haskell/hash2_y.ps cost cntr => http://sleepingsquirrel.org/haskell/hash2_c.ps ...but I have a hard time figuring out how to prevent something like "stg_ap_3_upd_info" or "void" cells from consuming so much memory. Anyone have pointers on how to best use the profile information? I'm still trying to digest "Heap Profiling for Space Efficiency" http://portal.acm.org/citation.cfm?id=734156 Are there any other related papers out there? (Of course it might be the case that I need a FiniteMap tutorial) Here's the code in question... import System (getArgs) import Data.FiniteMap main = do [n] <- getArgs let get fm k = lookupWithDefaultFM fm 0 k let keys = map (\x -> "foo_" ++ show x) [0..9999] let hash1 = listToFM $ zip keys [0..9999] let hash2 = listToFM $ zip keys (repeat 0) let update k fm = addToFM_C (+) fm k (get hash1 k) let res = foldr update hash2 (concat $ replicate (read n) keys) putStrLn $ unwords $ map show [get hash1 "foo_1", get hash1 "foo_9999", get res "foo_1", get res "foo_9999"] Thanks, Greg Buchholz