---------- Forwarded message ---------- From: AROONALOK PYNE <aroonalok.p...@gmail.com> Date: Thu, Jun 11, 2015 at 2:25 PM Subject: Re: Issue with mcapply To: Rainer M Krug <rai...@krugs.de>
R version 3.0.2 (2013-09-25) Large value : 9999999 I rerun the code as c(10000000) for which your machine works fine but my code still hangs on reaching b(). I am running it from Linux Terminal. On Thu, Jun 11, 2015 at 2:15 PM, Rainer M Krug <rai...@krugs.de> wrote: > AROONALOK PYNE <aroonalok.p...@gmail.com> writes: > > > Please check this code : > > > > library(parallel) > > workerFunc <- function(n) { return(n^2) } > > a <- function(){ > > CurrentTime <- Sys.time() > > res <- lapply(values, workerFunc) > > TimeTaken <- Sys.time() - CurrentTime > > print(TimeTaken) > > } > > b <- function(){ > > CurrentTime <- Sys.time() > > numWorkers <- detectCores() > > res <- mclapply(values, workerFunc, mc.cores = numWorkers-2) > > TimeTaken <- Sys.time() - CurrentTime > > print(TimeTaken) > > } > > c <- function(n){ > > values <<- 1:n > > print("Evaluating a : ") > > a() > > print("Evaluating b : ") > > b() > > } > > > > For large values of n, the code calculates a() but the hangs indefinitely > > on reaching b(). How do I correct it ? > > I am using Ubuntu 14.04 and core i7 Processor > > Which version of R and what are "large values"? > > I just did the following successfully: > > ,---- > | > c(100) > | [1] "Evaluating a : " > | Time difference of 0.0002059937 secs > | [1] "Evaluating b : " > | Time difference of 0.02037406 secs > | > c(1000) > | [1] "Evaluating a : " > | Time difference of 0.001929998 secs > | [1] "Evaluating b : " > | Time difference of 0.01943302 secs > | > c(1000000) > | [1] "Evaluating a : " > | Time difference of 1.822959 secs > | [1] "Evaluating b : " > | Time difference of 1.46111 secs > | > c(10000000) > | [1] "Evaluating a : " > | Time difference of 23.55863 secs > | [1] "Evaluating b : " > | Time difference of 15.90938 secs > | > > `---- > > Cheers, > > Rainer > -- > Rainer M. Krug > email: Rainer<at>krugs<dot>de > PGP: 0x0F52F982 > -- *AROONALOK PYNE* BE Graduate Department Of Computer Science And Engineering Jadavpur University, Kolkata-32 India -- *AROONALOK PYNE* BE Graduate Department Of Computer Science And Engineering Jadavpur University, Kolkata-32 India [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.