[Haskell-cafe] Substantial (1:10??) system dependencies of runtime performance??

[Gwern Branwen]

On Sat, Feb 2, 2013 at 3:19 PM, Nick Rudnick <nick.rudnick at gmail.com> wrote:
> Roughly, I would say the differences in runtime can reach a factor as much
> as 1:10 at many times -- and so I am curious whether this subject has
> already been observed or even better discussed elsewhere. I have spoken to
> somebody, and our only plausible conclusion was that software like web
> browsers is able to somewhat aggressively claim system resources higher in
> the privilege hierarchy (cache?? register??), so that they are not available
> to other programs any more.

Maybe the Haskell program requires a lot of disk IO? That could easily
lead to a big performance change since disk is so slow compared to
everything else these days. You could try looking with 'lsof' to see
if the browser has a ton of files open or try running the Haskell
program with higher or lower disk IO priority via 'ionice'.

-- 
gwern
http://www.gwern.net