I've written a small quick and dirty ruby script: http://mawercer.de/run-tests.rb
for each package if enableParallelbuilding is not set yet it will build it three times: 1st to build all dependencies (with enableParallelbuilding) 2nd without enableParallelbuilding 3rd with enableParallelbuilding If all 3 succeed this means that building with enableParallelbuilding succeeded two times the build times are compared. If enableParallelbuilding is significant faster (more than 20%) better is set to true Some results are already available here: http://mawercer.de/cache Thus there are already 104 packages which might benefit significantly from being built in parallel. When the script is done (which may take some more days because my v-server only has 4 cores) I'll turn this into a patch. This only tests x86_64 builds. I also have to say that there are some builds which randomly fail rarely. (Eg ruby did once "make internal error", but I couldn't reproduce it doing 5 additional builds) Thus I'm even thinking about running up to two or three times in such cases - or to patch nix to redo the whole build up to x times if a regular expressions such as make token errors are encountered in the logs. People who think accuracy is most important will disable this feature anyway - but some like me sometimes just have to do rebuilds .. and they may just work more often than not. If you have any objections about such a patch adding many enableParallelbuilding = true; lines based on my results you should tell me and make me understand why. Marc Weber _______________________________________________ nix-dev mailing list nix-dev@lists.science.uu.nl http://lists.science.uu.nl/mailman/listinfo/nix-dev
