Displaying 20 results from an estimated 500 matches similar to: "issue with parallel package"
2003 Apr 25
4
Kinderman-Ramage (PR#2846)
Hi,
Our department has detected a bug in the implementation of the
Kinderman-Ramage generator for normal random variates in version
1.7.0, which can be seen from the below R session.
(Consecutive calls for chisq.test(...) always gives p-values very
close to 0.)
We have already encountered this bug in version 1.6.2
The error is in file
R-1.7.0/src/nmath/snorm.c
Here is a patch for this file to
2010 May 23
2
possible bug in formals
Hi,
I am a little bit surprised by the following output of
'formals'. Is this the intended behavior?
> f <- function(a=1,b=-1) { a+b }
> class(formals(f)$a)
[1] "numeric"
> class(formals(f)$b)
[1] "call"
Josef
--
-----------------------------------------------------------------------------
Josef Leydold | WU (Vienna University of Economics and
2006 Aug 31
1
Interface for package supplied random number generator
Hi,
As you probably know, there is a problem with the interface for adding uniform
random number generators in R (see by article in R News 5/2, November 2005).
There exists a mechanism called "user-supplied" that allows users of R
to run their own generator in R. However, there is no such mechanism for
package writers. Those who want to add their own generators abuse
2009 Oct 07
1
Buglet in qbeta?
Hi,
I sometimes play around with extreme parameters for distributions and
found that qbeta is not always monotone as the following example shows.
I don't know whether this is serious enough to submit a bug report (as
this example is near to the limitations of floating point arithmetic).
Josef
> x <- qbeta((0:100)/100,0.01,5)
> x
[1] 0.000000e+00 1.253990e-201 1.589622e-171
2018 Jun 21
1
DOCUMENTATION(?): parallel::mcparallel() gives various types of "Error in unserialize(r) : ..." errors if value is of type raw
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))
2018 Aug 31
2
Detecting whether a process exists or not by its PID?
On Fri, Aug 31, 2018 at 2:51 PM Tomas Kalibera <tomas.kalibera at gmail.com> wrote:
[...]
> kill(sig=0) is specified by POSIX but indeed as you say there is a race
> condition due to PID-reuse. In principle, detecting that a worker
> process is still alive cannot be done correctly outside base R.
I am not sure why you think so.
> At user-level I would probably consider some
2019 May 03
2
mccollect with NULL in R 3.6
On Thu, May 2, 2019 at 7:24 PM Tomas Kalibera <tomas.kalibera at gmail.com> wrote:
>
> On 5/1/19 12:25 AM, Gergely Dar?czi wrote:
> > Dear All,
> >
> > I'm running into issues with calling mccollect on a list containing NULL
> > using R 3.6 (this used to work in 3.5.3):
> >
> > jobs <- lapply(
> > list(NULL, 'foobar'),
>
2019 Apr 30
2
mccollect with NULL in R 3.6
Dear All,
I'm running into issues with calling mccollect on a list containing NULL
using R 3.6 (this used to work in 3.5.3):
jobs <- lapply(
list(NULL, 'foobar'),
function(x) mcparallel(identity(x)))
mccollect(jobs, wait = FALSE, timeout = 0)
#> Error in names(res) <- pnames[match(s, pids)] :
#> 'names' attribute [2] must be the same length as the vector
2019 May 03
1
Strange error messages from parallel::mcparallel family under 3.6.0
Dear All,
Since upgrading to 3.6.0, I've been getting a strange error messages
from the child process when using mcparallel/mccollect. Before filing a report in the Bugzilla, I want to figure out whether I had been doing something wrong all this time and R 3.6.0 has exposed it, or whether something else is going on.
# Background #
Ultimately, what I want to do is to be able to set a time
2013 Feb 07
1
How to NAMESPACE OS-specific importFrom?
I'd like to importFrom(parallel, mccollect, mcparallel) but on Windows these are
not exported because this
if(tools:::.OStype() == "unix") {
export(mccollect, mcparallel, mc.reset.stream, mcaffinity)
}
appears at src/library/parallel/NAMESPACE:6 of svn r61857. So should I be doing
if (tools:::.OStype() == "unix") {
importFrom(parallel, mccollect, mcparallel)
}
2016 Aug 30
1
mcparallel / mccollect
Hi there,
I've tried to implement an asynchronous job scheduler using
parallel::mcparallel() and parallel::mccollect(..., wait=FALSE). My
goal was to send processes to the background, leaving the R session
open for interactive use while all jobs store their results on the
file system. To keep track of the running jobs I've stored the process
ids and written a little helper to not spawn
2018 Aug 31
1
Detecting whether a process exists or not by its PID?
On Fri, Aug 31, 2018 at 3:35 PM Tomas Kalibera <tomas.kalibera at gmail.com> wrote:
>
> On 08/31/2018 03:13 PM, G?bor Cs?rdi wrote:
> > On Fri, Aug 31, 2018 at 2:51 PM Tomas Kalibera <tomas.kalibera at gmail.com> wrote:
> > [...]
> >> kill(sig=0) is specified by POSIX but indeed as you say there is a race
> >> condition due to PID-reuse. In
2015 Mar 25
2
nested parallel workers
Hi Simon,
I'm having trouble with nested parallel workers, specifically, forking
inside socket connections.
When mclapply is called inside a SOCK, PSOCK or FORK worker I get an
error in unserialize().
cl <- makeCluster(1, "SOCK")
fun = function(i) {
library(parallel)
mclapply(1:2, sqrt)
}
Failure occurs after multiple calls to clusterApply:
> clusterApply(cl, 1,
2015 Jun 20
2
Listing all spawned jobs/processed after parallel::mcparallel()?
QUESTION:
Is it possible to query number of active jobs running after launching
them with parallel::mcparallel()?
For example, if I launch 3 jobs using:
> library(parallel)
> f <- lapply(1:3, FUN=mcparallel)
then I can inspect them as:
> str(f)
List of 3
$ :List of 2
..$ pid: int 142225
..$ fd : int [1:2] 8 13
..- attr(*, "class")= chr [1:3] "parallelJob"
2015 Mar 30
2
nested parallel workers
On 03/25/2015 07:48 PM, Simon Urbanek wrote:
> On Mar 25, 2015, at 3:46 PM, Valerie Obenchain <vobencha at fredhutch.org> wrote:
>
>> Hi Simon,
>>
>> I'm having trouble with nested parallel workers, specifically, forking inside socket connections.
>>
>
> You simply can't by definition - when you fork *all* the workers share the same connection
2012 Dec 11
1
Bug in mclapply?
I've been using mclapply and have encountered situations where it gives
errors or returns incorrect results. Here's a minimal example, which gives
the error on R 2.15.2 on Mac and Linux:
library(parallel)
f <- function(x) NULL
mclapply(1, f, mc.preschedule = FALSE, mc.cores = 1)
# Error in sum(sapply(res, inherits, "try-error")) :
# invalid 'type' (list) of argument
2018 Aug 30
3
Detecting whether a process exists or not by its PID?
Hi, I'd like to test whether a (localhost) PSOCK cluster node is still
running or not by its PID, e.g. it may have crashed / core dumped.
I'm ok with getting false-positive results due to *another* process
with the same PID has since started.
I can the PID of each cluster nodes by querying them for their
Sys.getpid(), e.g.
pids <- parallel::clusterEvalQ(cl, Sys.getpid())
Is there
2018 Aug 31
0
Detecting whether a process exists or not by its PID?
On 08/31/2018 03:13 PM, G?bor Cs?rdi wrote:
> On Fri, Aug 31, 2018 at 2:51 PM Tomas Kalibera <tomas.kalibera at gmail.com> wrote:
> [...]
>> kill(sig=0) is specified by POSIX but indeed as you say there is a race
>> condition due to PID-reuse. In principle, detecting that a worker
>> process is still alive cannot be done correctly outside base R.
> I am not sure
2019 May 03
0
mccollect with NULL in R 3.6
On 5/3/19 3:04 PM, Gergely Dar?czi wrote:
> On Thu, May 2, 2019 at 7:24 PM Tomas Kalibera <tomas.kalibera at gmail.com> wrote:
>> On 5/1/19 12:25 AM, Gergely Dar?czi wrote:
>>> Dear All,
>>>
>>> I'm running into issues with calling mccollect on a list containing NULL
>>> using R 3.6 (this used to work in 3.5.3):
>>>
>>> jobs
2018 Aug 31
0
Detecting whether a process exists or not by its PID?
On 08/31/2018 01:18 AM, Henrik Bengtsson wrote:
> Hi, I'd like to test whether a (localhost) PSOCK cluster node is still
> running or not by its PID, e.g. it may have crashed / core dumped.
> I'm ok with getting false-positive results due to *another* process
> with the same PID has since started.
kill(sig=0) is specified by POSIX but indeed as you say there is a race