[Rd] Possible with enableJIT function

[luke-tierney at uiowa.edu]

Thanks. This should be resolved in R-devel(r72788) and R-patched
(r72789)

Best,

luke

On Mon, 12 Jun 2017, Berend Hasselman wrote:

>
>
> In this email to the R-help list: https://stat.ethz.ch/pipermail/r-help/2017-June/447474.html
> and in this question on Stackoverflow: https://stackoverflow.com/questions/44486643/nleqslv-memory-use-in-r
>
> Andrew Leach has raised a question about the memory usage of my package nleqslv.
> In a model with a loop within a function he has experienced continuously increasing memory usage
> by package nleqslv leading to an out of memory condition.
>
> I have been able to reproduce the continuously increasing memory usage with the following small example.
>
> <code>
> library(nleqslv,lib.loc="../nleqslv.Rcheck")
> library(pryr)
> dslnex <- function(x) {
>    y <- numeric(2)
>    y[1] <- x[1]^2 + x[2]^2 - 2
>    y[2] <- exp(x[1]-1) + x[2]^3 - 2
>    y
> }
> xstart <- c(x1=1.5,x2=2)
> nsims <- 10
> for(test_iter in seq_len(nsims)){
>    z <- nleqslv(xstart,dslnex,jacobian=NULL)
>    print(paste("nleqslv iteration",test_iter,"and memory used is",mem_used()))
> }
> memory.profile()
> gc()
> print(paste("At end memory used is", mem_used()))
> </code>
>
> The final output is
>
> <output>
> [1] "nleqslv iteration 1 and memory used is 28921288"
> [1] "nleqslv iteration 2 and memory used is 29133256"
> [1] "nleqslv iteration 3 and memory used is 29132992"
> [1] "nleqslv iteration 4 and memory used is 29134712"
> [1] "nleqslv iteration 5 and memory used is 29136432"
> [1] "nleqslv iteration 6 and memory used is 29138152"
> [1] "nleqslv iteration 7 and memory used is 29139872"
> [1] "nleqslv iteration 8 and memory used is 29141592"
> [1] "nleqslv iteration 9 and memory used is 29143312"
> [1] "nleqslv iteration 10 and memory used is 29145032"
>>
>> memory.profile()
>       NULL      symbol    pairlist     closure environment     promise
>          1        8554      194726        4230        1065        6534
>   language     special     builtin        char     logical     integer
>      51374          45         671        9786        8030       37258
>     double     complex   character         ...         any        list
>       2645           1       53795           0           0       18487
> expression    bytecode externalptr     weakref         raw          S4
>          1       14662        2233         592         593        1049
>> gc()
>         used (Mb) gc trigger (Mb) max used (Mb)
> Ncells 416340 22.3     750400 40.1   581181 31.1
> Vcells 726127  5.6    1308461 10.0  1191521  9.1
>> print(paste("At end memory used is", mem_used()))
> [1] "At end memory used is 29126472"
> </output>
>
> Indeed memory used increases in each pass of the for loop.
>
> I have added these two lines at the top of the code after the  library(pryr) invocation.
>
> library(compiler)
> oldJIT <- enableJIT(0)
>
> This resolves the issue in the sense that memory used remains constant after the first iteration.
> Output in the for loop is now:
> <output>
> [1] "nleqslv iteration 1 and memory used is 24487784"
> [1] "nleqslv iteration 2 and memory used is 24495816"
> [1] "nleqslv iteration 3 and memory used is 24495816"
> [1] "nleqslv iteration 4 and memory used is 24495816"
> [1] "nleqslv iteration 5 and memory used is 24495816"
> [1] "nleqslv iteration 6 and memory used is 24495816"
> [1] "nleqslv iteration 7 and memory used is 24495816"
> [1] "nleqslv iteration 8 and memory used is 24495816"
> [1] "nleqslv iteration 9 and memory used is 24495816"
> [1] "nleqslv iteration 10 and memory used is 24495816"
> </output>
>
> My questions are
>
> - is this a bug(let) in the JIT compiler?
> - if it isn't what would need to be changed in nleqslv.R in the package source? (I haven't a clue)
>
> regards
>
> Berend Hasselman
>
> My sessionInfo:
>
> R version 3.4.0 (2017-04-21)
> Platform: x86_64-apple-darwin15.6.0 (64-bit)
> Running under: macOS Sierra 10.12.5
>
> Matrix products: default
> BLAS: /Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRblas.0.dylib
> LAPACK: /Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRlapack.dylib
>
> locale:
> [1] en_IE.UTF-8/en_IE.UTF-8/en_IE.UTF-8/C/en_IE.UTF-8/en_IE.UTF-8
>
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
>
> loaded via a namespace (and not attached):
> [1] compiler_3.4.0
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>

-- 
Luke Tierney
Ralph E. Wareham Professor of Mathematical Sciences
University of Iowa                  Phone:             319-335-3386
Department of Statistics and        Fax:               319-335-3017
    Actuarial Science
241 Schaeffer Hall                  email:   luke-tierney at uiowa.edu
Iowa City, IA 52242                 WWW:  http://www.stat.uiowa.edu