[Rcpp-devel] Question on performance

[Dirk Eddelbuettel]

On 24 September 2018 at 08:48, Kyle Baron wrote:
| Here's an updated version of the Rcpp code with a single call:
| https://github.com/jesusfv/Comparison-Programming-Languages-Economics/compare/master...kylebmetrum:master
| 
| The comparison runs are here:
| https://github.com/kylebmetrum/Comparison-Programming-Languages-Economics/issues/1

Very nice! Will you file a PR?
 
| For typical a single run ....
| 
| Original Rcpp: 2.762
| New Rcpp: 0.878
| testclang: 0.686582
| 
| 
| Original Rcpp / testclang: 4.026239
| New Rcpp / testclang: 1.279883
| 
| Moving sourceCpp was a big improvement as suggested.  Also, changing from
| parens to brackets to access NumericVector sped things up.  And some
| improvement too from re-factoring so that there was just a
| single call to the compiled code.

Still puzzled by the remaining 27% ...

Dirk
| 
| Kyle
| 
| 
| 
| On Mon, Sep 24, 2018 at 2:24 AM Iñaki Ucar <iucar at fedoraproject.org> wrote:
| 
| >
| >
| > El dom., 23 sept. 2018 13:01, Iñaki Ucar <iucar at fedoraproject.org>
| > escribió:
| >
| >> Also you can try adding
| >>
| >> // [[Rcpp::plugins(unwindProtect)]]
| >>
| >> to InsideLoop.cpp. That should boost the performance too with the
| >> latest version of Rcpp.
| >>
| >
| > Taking a look now, and I realize there are just calls to C++, not to R.
| > So, please, forget about what I've said. The dangers of skimming through
| > code in a mobile device and speaking too soon.
| >
| > Iñaki
| >
| >
| >> Iñaki
| >
| >
| >> El dom., 23 sept. 2018 a las 12:46, Kyle Baron (<kyleb at metrumrg.com>)
| >> escribió:
| >> >
| >> >
| >> > I got mOutput mixed up with mResults in the last message; it mResults
| >> that gets created up front and then every iteration.
| >> >
| >> >
| >> https://github.com/jesusfv/Comparison-Programming-Languages-Economics/blob/master/RBC_Rcpp.R#L45
| >> >
| >> https://github.com/jesusfv/Comparison-Programming-Languages-Economics/blob/master/InsideLoop.cpp#L12
| >> >
| >> >
| >> >
| >> >
| >> >
| >> > On Sun, Sep 23, 2018 at 5:38 AM Kyle Baron <kyleb at metrumrg.com> wrote:
| >> >>
| >> >>
| >> >> It seems like the sourceCpp thing is the biggie.  That dropped about a
| >> second of the time from something like 2.7 to 1.7 seconds
| >> >>
| >> >> They also create mOutput and then re-create it every time it goes into
| >> InsideLoop
| >> >>
| >> https://github.com/jesusfv/Comparison-Programming-Languages-Economics/blob/master/RBC_Rcpp.R#L41
| >> >>
| >> https://github.com/jesusfv/Comparison-Programming-Languages-Economics/blob/master/InsideLoop.cpp#L12
| >> >>
| >> >> I just passed mOutput into InsideLoop and modified it there
| >> >>
| >> https://github.com/kylebmetrum/Comparison-Programming-Languages-Economics/commit/89015a72a0cf673739e83e38d4a545db4886b879
| >> >>
| >> >>
| >> >>
| >> >>
| >> >>
| >> >>
| >> >>
| >> >>
| >> >>
| >> >>
| >> >>
| >> >> On Sat, Sep 22, 2018 at 1:21 PM Dirk Eddelbuettel <edd at debian.org>
| >> wrote:
| >> >>>
| >> >>>
| >> >>> On 22 September 2018 at 12:36, Michael Weylandt wrote:
| >> >>> | I don't have time right now, but the offending line is here:
| >> >>> |
| >> >>> |
| >> https://github.com/jesusfv/Comparison-Programming-Languages-Economics/blob/master/RBC_Rcpp.R#L62
| >> >>> |
| >> >>> | which calls `sourceCpp` repeatedly on each loop iteration.
| >> >>> |
| >> >>> | Should be a one line change to move it outside the loop and
| >> un-sully the
| >> >>> | good name of Rcpp.
| >> >>>
| >> >>> Nice catch!!  You should _definitely_ send him a PR. I also suggest
| >> to move
| >> >>> the sourceCpp() outside the timed segment as I do not think he
| >> accounts for
| >> >>> compilation in the other approaches (eg C++).
| >> >>>
| >> >>> Dirk
| >> >>>
| >> >>> --
| >> >>> http://dirk.eddelbuettel.com | @eddelbuettel | edd at debian.org
| >> >>> _______________________________________________
| >> >>> Rcpp-devel mailing list
| >> >>> Rcpp-devel at lists.r-forge.r-project.org
| >> >>>
| >> https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
| >> >>
| >> >>
| >> >>
| >> >>
| >> > _______________________________________________
| >> > Rcpp-devel mailing list
| >> > Rcpp-devel at lists.r-forge.r-project.org
| >> > https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
| >>
| >>
| >>
| >> --
| >> Iñaki Ucar
| >>
| >

-- 
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