From: Alan W. I. <ir...@be...> - 2017-08-08 11:38:47
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On 2017-08-08 09:57-0000 Arjen Markus wrote: > Hi Alan, > > > >> -----Original Message----- >> From: Alan W. Irwin [mailto:ir...@be...] >> Sent: Tuesday, August 08, 2017 11:46 AM >> >> So if you use make -j8 (or so) and ctest -j8 for your comprehensive test it will really >> go ~4 times faster because those -j options will utilize your four cores completely. >> But you have found in the past that the -j option gives unreliable results for both >> make and ctest for both the Cygwin and MinGW-w64/MSYS2 platforms. So you >> have dropped these -j options with the result that you only use one of your cores, >> but at least you do get slow but reliable results that way. >> > I explicitly use the build command "make" because of that, but I still see four instances of make running, as well as six instances of bash. This is with message "make VERBOSE=1 test_noninteractive in the installed examples build tree" as the last visible text. > > Not at all sure what this means, the information I get from the task manager does not reveal much about what these processes are actually doing (like in which directory etc.) The cmake application configures a recursive series of Makefiles, i.e., one make invokes another which invokes another. And likely the same is true of the shell (in this case bash) that is used to help execute eacho of those nested Makefile rules. So the real test would be provided by a cpu meter which would measure the activity of your 4 cpus. And I predict without the -j options that would show an average usage of 25 per cent for each of them or in other words you are only using 1/4th the power of your machine with no -j options. 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 __________________________ |