Building GHC for performance testing

[Edward Z. Yang]

Hello Johan,

Off the top of my head:

Technically speaking, the compiler does not have to be optimized to do
build tests; just the libraries.  So you could probably make the builds
run a bit faster this way.

Your command for nofib will only run the "standard" benchmarks;
to run, for example, the GC benchmarks, you will have to cd into
the gc directory and run make there.  You may also need to vary
the tests parameters in other ways, such as threaded and un-threaded.

Cheers,
Edward

Excerpts from Johan Tibell's message of 2014-03-06 01:50:09 -0800:
> Hi,
> 
> I'd like to set up a performance build bot for GHC, but before I can do
> that I need a script that reliably builds GHC and runs nofib. Do we have
> such a script? Here's a strawman proposal for one:
> 
>     cabal install happy alex
>     git clone git://git.haskell.org/ghc.git
>     cd ghc
>     ./sync-all --nofib get
>     perl boot
>     ./configure
>     make
>     cd nofib
>     make clean
>     make boot
>     make -k mode=slow
> 
> Questions:
> 
>  * Does this look sensible?
>  * Is there a way to only build and run a subset of the benchmarks?
>  * Are there any tweaks to mk/build.mk we can do to make the build faster
> without compromising the results?
>  * Is there a way to do this in a cheap throwaway VM like travis-ci does?
> Could such a VM already provide GHC and the required libs to make the whole
> thing hermetic?