On 12/29/08, Srinivas Nedunuri wrote:

Could someone tell me what the expected accuracy of the Haskell profiler is? I get quite widely varying results for the amount of time spent on a given function across different runs (eg one random example, from 1.5% to 10%). I even upped the size of the dataset in an attempt to increase the accuracy.

[redirecting to ghc-users] I assume you mean the GHC profiler. It's normal when profiling any programs, Haskell or not, for timing numbers to vary. Memory allocation counts, however, should be stable across different runs.

Also a related q: why doesnt't the time spent in putStr show up?

You would have to rebuild your GHC libraries with the -auto-all flag in order to get cost centres attached to library functions (but this may defeat some optimizations). Cheers, Tim -- Tim Chevalier * http://cs.pdx.edu/~tjc * Often in error, never in doubt "It's okay to be mean to the evil people who make life unbelievable, but try to be nice to me." -- Nerissa Nields