simonmarhaskell:
Donald Bruce Stewart wrote:
Had a go today building GHC on a multcore linux box, with -j, just to see how fast it would go.
Summary: you can build GHC from scratch in less than 10 minutes these days!
More details here: http://cgi.cse.unsw.edu.au/~dons/blog/2006/12/03#build_ghc_fast
I'd be interested in how long it takes if you turn on -O for the stage 1 compiler only. The point being that it'll be slower to compile stage 1, but that compiler is then used to build all the libraries and stage 2, so the benefit of having an optimised stage 1 might outweigh the time it takes to build it.
Yes! 7 mins 49 seconds, with: SRC_HC_OPTS = -H64m -Onot -fasm GhcStage1HcOpts = -O -fasm GhcStage2HcOpts = -Onot -fasm GhcLibHcOpts = -Onot -fasm GhcLibWays = SplitObjs = NO and -j10, on a 4 core linux machine. When the new 16 core box arrives, I'll set up a nightly build to ensure the -jN building keeps working. -- Don