Thanks Pierre. The profile results, especially the zoom profiler screen shot, show that virtually all of the CPU time being consumed is from bash and its child processes. The system is otherwise idle with no other processes running to any significant degree. My system is ~99.5% idle when I'm not running the test, and ~91.5% idle when the test is running.
Even when I do run other processes simultaneously they don't slow down the bash/expr task because with twelve hardware threads there are lots to go around. -----Original Message----- From: Pierre Gaston [mailto:pierre.gas...@gmail.com] Sent: Tuesday, March 19, 2013 2:00 AM To: Bruce Dawson Cc: bug-bash@gnu.org; b...@packages.debian.org Subject: Re: Bug/limitation in 'time' (kernel setings?)... On Tue, Mar 19, 2013 at 5:03 AM, Bruce Dawson <brucedaw...@cygnus-software.com> wrote: > I'll give those a try. > > BTW, I just posted the blog post to share what I'd found. You can see > it > here: > > http://randomascii.wordpress.com/2013/03/18/counting-to-ten-on-linux/ > > I hope it's accurate, and I do think it would be worth mentioning the > issue in the documentation for 'time' and the bash 'time' internal command. > For what it's worth, I still thinks that time is not lying (though the man page warns about possible inaccuracies), Your loop with expr might be "cpu bound" but it does not run often because other processes are given a chance to run.
