On 2013-05-20 11:52-0500 Kenneth Boyd wrote:
Can somebody with access to MSYS bash.exe on Microsoft Windows verify that startup latency by timing "--version" options for standard commands such as cmake? If such times on a normal PC are hundreds of milliseconds than you have confirmed the issue, but if they are only a few milliseconds (8 on Linux, for example, for my entry level PC hardware), then you have shown the issue doesn't exist for Microsoft Windows which would contradict the above inefficient fork explanation.
sh-3.1$ time gcc --version gcc.exe (4.3.3-tdm-1-dw2 mingw32) 4.3.3-dw2 Copyright (C) 2008 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. real 0m0.028s user 0m0.000s sys 0m0.015s Kenneth
Here are the corresponding (second-time) numbers here for Linux and Wine. software@raven> time gcc --version gcc (Debian 4.7.2-5) 4.7.2 Copyright (C) 2012 Free Software Foundation, Inc. [...] real 0m0.002s user 0m0.000s sys 0m0.000s That 0.002 seconds is so small that is probably only reliable within a factor of two or so but indicates gcc --version has hardly any overhead at all on Linux. bash.exe-3.1$ time gcc --version gcc.exe (GCC) 4.7.0 Copyright (C) 2012 Free Software Foundation, Inc. [...] real 0m0.176s user 0m0.000s sys 0m0.040s That is an ugly factor of 90 or so compared to the Linux result. Your own value is 14 times my Linux value but 1 sixth my MSYS/Wine value so it is hard to interpret it. Do you have an equivalent result on your hardware for Linux? Alan __________________________ Alan W. Irwin Astronomical research affiliation with Department of Physics and Astronomy, University of Victoria (astrowww.phys.uvic.ca). Programming affiliations with the FreeEOS equation-of-state implementation for stellar interiors (freeeos.sf.net); the Time Ephemerides project (timeephem.sf.net); PLplot scientific plotting software package (plplot.sf.net); the libLASi project (unifont.org/lasi); the Loads of Linux Links project (loll.sf.net); and the Linux Brochure Project (lbproject.sf.net). __________________________ Linux-powered Science __________________________ -- Powered by www.kitware.com Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the CMake FAQ at: http://www.cmake.org/Wiki/CMake_FAQ Follow this link to subscribe/unsubscribe: http://www.cmake.org/mailman/listinfo/cmake
