Hi, On Tue, 5 Apr 2016 23:18:41 -0500 Steven Stallion <sstall...@gmail.com> wrote:
> All, > > I am currently working on a very large project that contains over 500 > (yes, really) listfiles. A co-worker was looking into some performance > issues we were seeing during configuration and found something very > interesting. Currently configuration is taking 1m57s across several > configurations using Mac OS X as a host and the latest .dmg from > cmake.org (3.5.1). > > We have a core module that provides a number of helper functions and > macros (completely stateless) that is included by most of this > listfiles (nearly 400 of them). We found that an include guard was > missing, after adding that configuration now clocks in at 1m30s. > > Taking things a step further, we removed includes of the module, and > simply included it once in the top-level listfile. Configuration then > dropped to about 55s. > > The results above seem to indicate a possible file I/O bottleneck. > This is very surprising to me - these builds are being run on recent > core-i7's with SSDs. Is anyone else on the list dealing with large > projects or similar configuration issues? LLVM/Clang is using ~330 CMakeLists.txt - I never noticed the config-step to be a bottleneck (cmake ../llvm takes 10 seconds on my system). But LLVM/Clang is not including a lot of Modules. real 0m10.551s user 0m6.696s sys 0m1.576s Maybe it is more a question of LOC of than the number of files. regards, -- Patrick. -- Powered by www.kitware.com Please keep messages on-topic and check the CMake FAQ at: http://www.cmake.org/Wiki/CMake_FAQ Kitware offers various services to support the CMake community. For more information on each offering, please visit: CMake Support: http://cmake.org/cmake/help/support.html CMake Consulting: http://cmake.org/cmake/help/consulting.html CMake Training Courses: http://cmake.org/cmake/help/training.html Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Follow this link to subscribe/unsubscribe: http://public.kitware.com/mailman/listinfo/cmake
