Building GHC for performance testing

[Simon Marlow]

On 06/03/14 09:50, Johan Tibell wrote:
> 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
> <http://git.haskell.org/ghc.git>
>      cd ghc
>      ./sync-all --nofib get
>      perl boot

./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 <http://build.mk> we can do to
> make the build faster without compromising the results?

Turn down the stage2 optimisation, and turn off the docs:

GhcStage2HcOpts = -O
HADDOCK_DOCS       = NO
BUILD_DOCBOOK_HTML = NO
BUILD_DOCBOOK_PS   = NO
BUILD_DOCBOOK_PDF  = NO

>   * 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?

Sure.  I occasionally use EC2 for GHC hacking and I had a VM set up with 
all the tools ready to work on GHC.  (but I assume you mean a local VM; 
EC2 is not good for perf measurements)

Cheers,
Simon