similar to: 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

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"

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

Hi Andreas, thank you very much, good job finding it was EBADF. Now the question is why the pipe has been closed prematurely; it could be accidentally by R (a race condition in the cleanup code in fork.c) or possibly by some other code running in the same process (maybe the R program itself or some other code it runs). Maybe we can take this off the list and come back when we know the cause

Hi Andreas, the error is reported when some child process cannot send results to the master process, which originates from an error returned by write() - when write() returns -1 or 0. The logic around the writing has not changed since R 3.5.2. It should not be related to the printing in the child, only to returning the value. The problem may be originating from the execution environment,

Moritz Muehlenhoff writes ("Re: Xen package security updates for jessie 4.4, XSA-213, XSA-214"): > Yes, the distribution line should be jessie-security, but please send > a debdiff to team at security.debian.org for a quick review before > uploading (I have no idea whether dgit supports security-master). Here is the proposed debdiff (actually, a git diff) for xen in jessie. My

Hi all, With the help of Tomas, I was able to track the issue down: Prior to R v3.6.0 the parallel package passes an uninitialized variable as the file descriptor argument to the close system call. In my particular R session this uninitialized variable (reproducibly) was holding the value 7, which corresponded to the file descriptor of the write end of the pipe the second child would use to

Hi all, With the help of Tomas, I was able to track the issue down: Prior to R v3.6.0 the parallel package passes an uninitialized variable as the file descriptor argument to the close system call. In my particular R session this uninitialized variable (reproducibly) was holding the value 7, which corresponded to the file descriptor of the write end of the pipe the second child would use to

Hi, I am facing a very weird problem with parallel::mclapply. I have a script which does some data wrangling on an input dataset in parallel and then writes the results to disk. I have been using this script daily for more than one year always on an EC2 instance launched from the same AMI (no updates installed after launch) and processed thousands of different input data sets successfully. I now

The original implementation utilies select(). In Linux select() typically supports up to 1024 file descriptors. This can be a problem when user tries to boot up many guests. Switching to poll() has minimum impact on existing code and has better scalibility. Up to 8192 file descriptors are supported in the current implementation. Signed-off-by: Wei Liu <wei.liu2@citrix.com> ---

Moritz Muehlenhoff writes ("Re: Xen package security updates for jessie 4.4, XSA-213, XSA-214"): > On Thu, May 04, 2017 at 05:06:07PM +0100, Ian Jackson wrote: > > I have fixed these in stretch but the jessie package remains unfixed. > > I think I may be able to find some backports somewhere. Would that be > > useful ? Is anyone else working on this ? > >

Dear R developers: ... 7: lapply(seq_len(cores), inner.do) 8: FUN(1:3[[3]], ...) 9: sendMaster(try(lapply(X = S, FUN = FUN, ...), silent = TRUE)) Selection: .....................Error in sendMaster(try(lapply(X = S, FUN = FUN, ...), silent = TRUE)) : long vectors not supported yet: memory.c:3100 admittedly, my outcome will be a very big list, with 30,000 elements, each containing data frames

Hi, on my system (Linux 2.6.18.8 - ia64), if a domain write on the xencons before xenconsole is initialized the domain gets back what it wrote. This patch fixes this issue by making raw the pty slave very early. (I suppose it doesn''t happen with linux as a guest because it takes a little bit of time before writing to xencons). Tristan. _______________________________________________

Hi Tomas, Thanks for your prompt reply and your offer to help. I might need to get back to this since I am not too experienced in debugging these kinds of issues. Anyway, I gave it a try and I think I have found the immediate cause: I installed the debug symbols (r-base-core-dbg), placed https://github.com/wch/r-source/blob/tags/R-3-5-2/src/library/parallel/src/fork.c in cwd and changed the

Folks, First, let me thank everyone involved for making QEMU available on the Solaris platform. It''s turning out to be really handy.... Here at work we''re required to use GroupWise calendaring (at least for the time being), and I''m trying to get a bit more organized, so thought I''d start (again) using a Palm handheld to take my calendar, etc. with me. The new

Hello I want to predict the future values of time series with Garch When I specified my model like this: library(fGarch) ret <- diff(log(x))*100 fit = garchFit(~arma(1,0,0)+garch(1, 1), data =ret) predict(fit, n.ahead = 10) meanForecast meanError standardDeviation 1 0.01371299 0.03086350 0.03305819 2 0.01211893 0.03094519 0.03350248

Dear fellow R users, I am experiencing some problem using function mclapply from recommended R package parallel. This problem is a bit "deep in source code" (maybe r-devel list would be more appropriate ?). Actually, I have noticed on a specific Linux HPC system that the various readChild() calls in mclapply did not end the children processes, as would be expected (ie compared to what

I stumbled upon the following: f <- parallel::mcparallel(raw(0L)) parallel::mccollect(f) # $`77083` # NULL but f <- parallel::mcparallel(raw(1L)) parallel::mccollect(f) # Error in unserialize(r) : read error traceback() # 2: unserialize(r) # 1: parallel::mccollect(f) (restarting because the above appears to corrupt the R session) f <- parallel::mcparallel(raw(2L))

Hi Dirk, Thanks for the solution. Now I know the work-arounds, but still don't quite get it. Why does R_DEFAULT_PACKAGES has anything to do with library(methods)? If library(h5) works, it should just work, not depend on an environment variable. Rscript is not consistent with R, that's my confusion. Steve 2017-12-26 20:46 GMT+08:00 Dirk Eddelbuettel <edd at debian.org>: >

Hello everyone, I'm trying to parallelize an R script I have written. To do this, I am first trying to use the multicore package, because I've had some previous success with that. The function I'm trying to parallelize is illumqc. I'd like to create a separate process for each of 8 files, contained in the vector "files". Below is my code: for(i in