You asked several questions. Elapsed: yes User + System = CPU: yes Finally: You have to look at the load and/or cpu core count. Unless you setup your code to take advantage of multiple cores, R runs on a single core. Also: Do you really need to ask that question?
--------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity. Mark Leeds <marklee...@gmail.com> wrote: >Hi : I looked at the help for system.time but I still have the >following >question. Can someone explain the output following output >of system.time : > > user system elapsed >12399.681 5632.352 56935.647 > >Here's my take based on the fact that I was doing ps -aux | grep R off >and >on and the total amount of CPU minutes that >got allotted before the job ended was about 5 hours and the total >actual >time that the job took was about 15 hours. > >Does elapsed = total actual time job taken ? That seems to be the case >or a >strange coincidence. > >Does user + system = CPU time from ps -aux | grep R ? That seems to be >the >case also or a weird coincidence. > >Finally, why can't the CPU get a higher percentage ? It's seems like >it's >always around 30% which would make sense since >5 is ~ 30% of 15 hours. > >Also, assuming my take above is correct, when talking about timing of >algorithms, in this case, does one say the job took 5 hours or 15 hours >? >I'm trying to see how fast an algorithm is compared to others and I'm >not >sure what the standard is. I'm on fedora 16.0 and using R 2.15. >Thanks. > > [[alternative HTML version deleted]] > >______________________________________________ >R-help@r-project.org mailing list >https://stat.ethz.ch/mailman/listinfo/r-help >PLEASE do read the posting guide >http://www.R-project.org/posting-guide.html >and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.