Re: -prof, -threaded, and -N

From https://github.com/ghc/ghc/blob/master/rts/RtsFlags.c#L1238 it seems that the behavior described in my email below is intended: ``` if (rts_argv[arg][2] == '\0') { #if defined(PROFILING) RtsFlags.ParFlags.nNodes = 1; #else RtsFlags.ParFlags.nNodes = getNumberOfProcessors(); #endif ``` So, my question is: what is the reason for this difference between the profiling and the non-profiling case? Lars

On Jun 2, 2015, at 10:20 PM, Lars Kuhtz wrote:

Hi,

The behavior of the -N flag (without argument) with the profiling runtime seems inconsistent compared to the behavior without profiling. The following program

``` module Main where

import GHC.Conc

main :: IO () main = print numCapabilities ```

when compiled with `ghc -threaded -fforce-recomp Prof.hs` and run as `./Prof +RTS -N` prints `2` on my machine. When the same program is compiled with `ghc -threaded -fforce-recomp -prof Prof.hs` and executed as `./Prof +RTS -N` it prints `1`.

When an argument is provided to `-N` (e.g. `./Prof +RTS -N2`) the profiling and non-profiling versions behave the same.

I tested this with GHC-7.10.1 but I think that I already observed the same behavior with GHC-7.8.

Is this inconsistency intended?

Lars _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/glasgow-haskell-users