[R-pkg-devel] Slowdown running examples since 4.2 on Windows

[Tomas Kalibera]

On 6/29/22 22:25, Barbara Lerner wrote:
> I have a package that I want to submit an updated version for but the
> examples run too slowly on win-builder since 4.2 came out.  I just
> submitted the exact same tar.gz file to all 3 versions of R available on
> win-builder and got the results shown below.  Notice the dramatic
> slowdown from 4.1.3 to 4.2.1.
>
> I don't know how to go about tracking down the cause of this slowdown.
> The examples are quite small.  I am reluctant to use \dontrun, but I am
> not sure what else to do.

Could you perhaps submit to Winbuilder several times (with some 
non-trivial delay between the runs) to see if the very long execution is 
reproducible?

If so, the next step could be trying on a Windows machine with 
interactive access, to reproduce, and if it is still so slow, checking 
where the time is spent, using an R profiler, using some C profiler 
(e.g. VerySleepy is free), comparing possibly to 4.1.3. It might be 
useful or necessary to also do the profiling with a debug build of 
Windows and/or the package, while the performance numbers will be 
skewed, one would see the symbol names.

If you wanted specific help, please send a reproducible example - 
instructions how to run the code and which code.

Best
Tomas

>
> June 29 2:33 PM  - old release
> * using R version 4.1.3 (2022-03-10)
> i386 timings
> name	user	system	elapsed
> prov.json	3.28	0.33	5.19	
> prov.run	2.70	0.27	4.18	
>
> x64 timings
> name	user	system	elapsed
> prov.json	3.51	0.27	4.93	
> prov.run	3.05	0.28	4.48	
>
>
> June 29 2:19 PM  - release
> * using R version 4.2.1 (2022-06-23 ucrt)
> * using platform: x86_64-w64-mingw32 (64-bit)
> name	user	system	elapsed
> prov.json	16.98	8.81	26.82	
> prov.run	3.53	0.42	4.89
>
>
> June 29  1:52 PM - devel
> * using R Under development (unstable) (2022-06-28 r82534 ucrt)
> * using platform: x86_64-w64-mingw32 (64-bit)
> name	user	system	elapsed
> prov.json	16.60	 9.09	26.66	
> prov.run	3.57	0.22	4.70 I then ran the same timing script as win-builder uses on my Mac,
> using Rscript and got these results: name    user    system  elapsed
> prov.json       1.105   0.159   1.329 prov.run        0.890   0.103
> 1.053 session_info reports:  version  R version 4.2.0 (2022-04-22)
>    os       macOS Catalina 10.15.7  system   x86_64, darwin17.0 I then
> installed 4.2.1 on my Mac. The time is a little slower but nothing like
> the slowdown on Windows.
> name    user    system  elapsed prov.json       1.286   0.230   3.080
> prov.run        0.940   0.108   1.131  version  R version 4.2.1
> (2022-06-23)  os       macOS Catalina 10.15.7  system   x86_64, darwin17.0
>