From tomas.kalibera at gmail.com  Mon Feb 12 09:24:06 2018
From: tomas.kalibera at gmail.com (Tomas Kalibera)
Date: Mon, 12 Feb 2018 09:24:06 +0100
Subject: [Rd] makeCluster hangs
In-Reply-To: <18085b5b-f50e-215d-e879-da94cf1ffcb1@ur.rochester.edu>
References: <d5cb6887-2745-8e8a-a510-302ad736dbad@ur.rochester.edu>
 <CAFDcVCT3LvyfHa+duqD-sjbrr07cgoZ_Z=HymouOP8neWRGdKQ@mail.gmail.com>
 <18085b5b-f50e-215d-e879-da94cf1ffcb1@ur.rochester.edu>
Message-ID: <e2d43660-78f3-370d-2b36-a0962a4ff790@gmail.com>

Also using R-devel might help - the forking support in parallel has been 
made more robust against race conditions, but the changes are probably 
too substantial to port to 3.4.x. If you find how to cause a race 
condition using parallel/forking in R-devel, a report would be greatly 
appreciated.

Tomas

On 02/11/2018 09:51 PM, T. Florian Jaeger wrote:
> Dear Henrik,
>
> thank you, for the quick reply. Bizarrely enough, the problem vanished when
> I woke the computer from sleep (I had previously replicated the problem
> after several restarts of both R and the MacOS).
>
> I will follow-up if I can again replicate the problem.
>
> Florian
>
>
> On 2/10/18 4:39 PM, Henrik Bengtsson wrote:
>> A few quick comments:
>>
>> * You mention R --vanilla, but make sure to try with
>> parallel::makeCluster(), so that you don't happen to pick up
>> snow::makeCluster() if 'snow' is attached and ahead of parallel on the
>> search() path.
>>
>> * Try creating a single background worker, i.e. parallel::makeCluster(1L).
>>
>> * Try with cl <- future::makeClusterPSOCK(1L, verbose = TRUE), which
>> gives the same thing, but it also show you some details on what it
>> does internally; that may give some clues where it stalls.
>>
>> /Henrik
>>
>> On Sat, Feb 10, 2018 at 12:11 PM, T. Florian Jaeger
>> <fjaeger at ur.rochester.edu> wrote:
>>> Hi all,
>>>
>>> I can't get the functionality of the package parallel to work. Specifically,
>>> makeCluster() hangs when I run it. I first noticed the problem when trying
>>> to run Rstan with multiple cores and the traced it back to the core package
>>> parallel. The following results in R hanging after the call to makeCluster.
>>>
>>> library(parallel)
>>>
>>> # Calculate the number of cores
>>> no_cores <- detectCores() - 1
>>>
>>> # Initiate cluster
>>> cl <- makeCluster(no_cores)
>>>
>>> I'm running MacOS High Sierra 10.13.3 (17D47) on a MacbookPro 2017 laptop
>>> with 4 cores.
>>>
>>> platform       x86_64-apple-darwin15.6.0
>>> arch           x86_64
>>> os             darwin15.6.0
>>> system         x86_64, darwin15.6.0
>>> status
>>> major          3
>>> minor          4.3
>>> year           2017
>>> month          11
>>> day            30
>>> svn rev        73796
>>> language       R
>>> version.string R version 3.4.3 (2017-11-30)
>>> nickname       Kite-Eating Tree
>>>
>>> The problem replicates in R --vanilla
>>>
>>>
>>> I've spent hours googling for solutions but can't find any reports of this
>>> problem. Any help would be appreciated.
>>>
>>>
>>> Florian
>>>
>>> ______________________________________________
>>> R-devel at r-project.org mailing list
>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__stat.ethz.ch_mailman_listinfo_r-2Ddevel&d=DwIBaQ&c=kbmfwr1Yojg42sGEpaQh5ofMHBeTl9EI2eaqQZhHbOU&r=O6dqVFPEDpdoXY3wkv8u6o0LHKx4WbQ_itn0O87jj5s&m=R7DIWWqYTP2xarhrvKcymtN3XlAQ9vHLFDhPL6FxQ60&s=7F8Lez-XE8iC2JBU4JYsEtF3U0HObhMnCASud5xTgNM&e=
>> .
>>



[Rd] makeCluster hangs
Tomas Kalibera