Displaying 20 results from an estimated 200 matches similar to: "Problem with mclapply in package parallel"
2012 Apr 06
1
Compatibility problem with R-2.9.0 and R-2.14.0
Hello all,
Using classical glm function with binomial family, I experienced a problem when using predict() over
a glm object.
I found that family objects built on R-2.14.0 contain elements like :
.Call(C_logit_link,...)
But on R-2.9.0, the object C_logit_link can not be found. Instead, this prior version used to call
more simply :
.Call("logit_link",...)
which causes no problem.
Is
2010 Sep 23
1
strange behaviour of callNextMethod in S4 methods
Hello,
I experienced a strange behaviour of callNextMethod when used in either
initialize or any other S4 function method definition.
Help says callNextMethod calls the next inherited method for the current
function from where it is called with the same actual (non missing)
arguments. This is OK. The problem appears when some formal arguments
(in particular, S4 objects) of this function are
2013 Jan 22
2
Length of seed for l'Ecuyer-CMRG
Dear expeRts,
./src/library/base/man/Random.Rd says that L'Ecuyer requires a seed of length 6.
./src/library/parallel/man/RngStream.Rd also mentions this, but only in the text
part; In the "Arguments"-part, it says that "seed" has to be of length 7
Also:
,----
| > RNGkind("L'Ecuyer-CMRG")
| > length(.Random.seed)
| [1] 7
`----
Is the docu old? Some
2011 Dec 10
0
clusterSetRNGStream() question
In a vanilla R 2.14.0 GUI session (on Windows XP SP3):
> library(parallel)
> cl<-makePSOCKcluster(2)
> RNGkind()
[1] "Mersenne-Twister" "Inversion"
> clusterSetRNGStream(cl)
> RNGkind()
[1] "L'Ecuyer-CMRG" "Inversion"
> stopCluster(cl)
Is it intentional that clusterSetRNGStream() changes the RNG kind in
the master process?
2019 May 19
2
Race condition on parallel package's mcexit and rmChild
I've been hacking with parallel package for some time and built a
parallel processing framework with it. However, although very rarely,
I did notice "ignoring SIGPIPE signal" error every now and then.
After a deep dig into the source code, I think I found something worth
noticing.
In short, wring to pipe in the C function mc_exit(SEXP sRes) may cause
a SIGPIPE. Code from
2019 May 20
1
Race condition on parallel package's mcexit and rmChild
Have read the latest code, but I still don't understand why mc_exit
needs to write zero on exit. If a child closes its pipe, parent will
know that on next select.
Best,
Yijiang
Tomas Kalibera <tomas.kalibera at gmail.com> ?2019?5?20??? ??10:52???
>
> This issue has already been addressed in 76462 (R-devel) and also ported
> to R-patched. In fact rmChild() is used in
2019 May 20
0
Race condition on parallel package's mcexit and rmChild
I've been hacking with parallel package for some time and built a
parallel processing framework with it. However, although very rarely,
I did notice "ignoring SIGPIPE signal" error every now and then.
After a deep dig into the source code, I think I found something worth
noticing.
In short, wring to pipe in the C function mc_exit(SEXP sRes) may cause
a SIGPIPE. Code from
2019 May 20
0
Race condition on parallel package's mcexit and rmChild
This issue has already been addressed in 76462 (R-devel) and also ported
to R-patched. In fact rmChild() is used in mccollect(wait=FALSE).
Best
Tomas
On 5/19/19 11:39 AM, Sun Yijiang wrote:
> I've been hacking with parallel package for some time and built a
> parallel processing framework with it. However, although very rarely,
> I did notice "ignoring SIGPIPE signal"
2012 Nov 02
1
An idea: Extend mclapply's mc.set.seed with an initial seed value?
Hello,
Have been thinking that sometimes users may want each process to initialize
its random seed with a specific value rather then the current seed. This
could be keyed off depending whether mc.set.seed is logical, preserving the
current behaviour, or numerical, using the value in a call to set.seed.
Does this make sense?
If you wonder how I came up with the idea: I spent a couple of hours
2012 Nov 04
0
parallel::mclapply list coercion limits opportunities for code re-use?
The attached diff address the following issues in mclapply
mclapply coerces non-lists or objects (S3 or S4) to lists, but a list may not be
an efficient representation and is not required if the object implements length,
[, and [[ methods (lapply must also work on the object, either through coercion
to a list at the 'inner.do' level or through other means, e.g., promoting lapply
to a
2012 Dec 29
1
parallel error message extraction (in mclapply)?
dear R experts---I am looking at a fairly uninformative error in my program:
Error in mclapply(1:nrow(opts), solveme) :
(converted from warning) all scheduled cores encountered errors in user code
the doc on ?mclapply tells me that
In addition, each process is running the job inside try(...,
silent=TRUE) so if error occur they will be stored as try-error
objects in the list.
I looked up
2010 Aug 12
1
multicore mclapply error
I'm running r 2. on a mac running 10.6.4 and a dual-core macbook pro. I'm having a funny time with multicore. When I run it with 2 cores, mclapply, R borks with the following error.
The process has forked and you cannot use this CoreFoundation functionality safely. You MUST exec().
Break on __THE_PROCESS_HAS_FORKED_AND_YOU_CANNOT_USE_THIS_COREFOUNDATION_FUNCTIONALITY___YOU_MUST_EXEC__()
2012 Dec 13
1
possible bug in function 'mclapply' of package parallel
Dear parallel users and developers,
I might have encountered a bug in the function 'mclapply' of package
'parallel'. I construct a matrix using the same input data and code with a
single difference: Once I use mclapply and the other time lapply.
Shockingly the result is NOT the same.
To evaluate please unpack the attached archive and execute
Rscript mclapply_test.R
I put the
2011 Apr 11
1
Mclapply and print statement
Dear all.
I am using the mclapply function to split my code to the many cores my system has. It seems that is working fine. This is the parallel version of lcapply.
The only problem that I seem to have is that the printf cannot print messages.
The ideal to me is to have fro my function an output of the form
Shadowlist<-mclapply(1:dimz, function(i) {
print(sprintf('Creating the
2020 Oct 08
2
exiting mclapply early on error
Hey folks,
Is there any way to exit an mclapply early on error?
For example, in the following mclapply loop, I have to wait for all the processes to finish before the error is returned.
```
mclapply(X = 1:12, FUN = function(x) {Sys.sleep(0.1); if(x == 4) stop()}, mc.cores = 4, mc.preschedule = F)
```
When there are many calculations in FUN, it takes a long time before the error is returned.
2020 Oct 09
0
exiting mclapply early on error
Hello Giovanni,
I don't know if my workflow would suit you but I tend to want the
opposite when I launch a parallel process. I tend to want to keep the
processes alive as long as they can. If the computation time is long I
would not want to lose everything.
lapply..8 <- function(X,FUN,...){
max..cores <- as.numeric(system("grep ^processor /proc/cpuinfo 2>/dev/null | wc
2020 Oct 13
1
exiting mclapply early on error
Thanks for the response, Jeremie. I wholeheartedly agree about testing.
In my case, this feature would be used purely to reduce computation time. I?m calculating
an expensive (and embarrassingly parallel) likelihood function, and for some parameter combinations
my objective function diverges to infinity. In those instances, I?d like to throw an error that stops
subsequent computations and that I
2009 Aug 10
1
multicore mclapply hangs
When I execute mclapply it creates the needed processes, but these
processes never begin computing anything, they just wait indefinitely.
I recently upgraded to version 2.9.1, which might have caused the problem.
--
Med venlig hilsen
Rune Schjellerup Philosof
Ph.d.-studerende, Statistik, IST, SDU
Telefon: 6550 3607
E-mail: rphilosof at health.sdu.dk
Adresse: J.B. Winsl?wsvej 9, 5000 Odense
2012 Nov 16
0
Bug in parallel / mclapply
Hi,
there seem to be some (small) bugs in the mclapply function in parallel.
I discovered this in the current R release version, and I checked that it is
still present in R-devel.
I think it only occurs in the part of the code corresponding to argument option
mc.preschedule = FALSE.
Here are two examples:
a)
library(parallel)
mclapply(list(), identity, mc.preschedule=FALSE)
Error in
2015 Sep 02
0
mclapply memory leak?
Well it's only a leak if you don't get the memory back after it returns,
right?
Anyway, one (untested by me) possibility is the copying of memory pages
when the garbage collector touches objects, as pointed out by Radford Neal
here:
http://r.789695.n4.nabble.com/Re-R-devel-Digest-Vol-149-Issue-22-td4710367.html
If so, I don't think this would be easily avoidable, but there may be