Initial compile time benchmarks

Ömer Sinan Ağacan omeragacan at
Thu Mar 31 16:00:42 UTC 2016

Hi Joachim,

That's GHC HEAD at the time with -O1 for stage 2 + libs.

The way I generate the logs is:

- I create a cabal sandbox and run `cabal exec zsh` to set up the env

- I install packages in that shell.

- $ (cat  .cabal-sandbox/logs/*.log | analyze-ghc-timings) > output

I don't know why there would be that much difference. Note that my setup was
not perfect, I run some other (although lightweight) processes on the side.

2016-03-31 4:49 GMT-04:00 Joachim Breitner <mail at>:
> Hi Ömer,
> thanks for the log. This is roughly GHC HEAD, right?
> I wanted to check for low-hanging fruit in “my” code, so I compiled
> Data.Reflection, where your tool reports 12% time spent in Call Arity.
> But if I run it with profiling, it says 3.5% of time is spent in that
> pass, and if I run your tool on the timing output produced by a
> profiled GHC, I get 8.3%, and on the output of a a development build, I
> get 3.8%.
> So what is your setup: How did you compile GHC, and with what options
> are you running it?
> Greetings,
> Joachim
> --
> Joachim “nomeata” Breitner
>   mail at joachim-breitner.de
>   XMPP: nomeata at • OpenPGP-Key: 0xF0FBF51F
>   Debian Developer: nomeata at
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