From simon.urbanek at r-project.org  Thu May  5 02:54:47 2016
From: simon.urbanek at r-project.org (Simon Urbanek)
Date: Wed, 4 May 2016 20:54:47 -0400
Subject: [Rd] R process killed when allocating too large matrix (Mac OS
	X)
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	<CAM3-Kja40deG=04U+PDNjLD=sHzQRiz_umia+wBEP77YyW5qQA@mail.gmail.com>
Message-ID: <C9469087-2FB7-45D3-956F-CF2A743AC13E@r-project.org>


On May 4, 2016, at 6:14 PM, Marius Hofert <marius.hofert at uwaterloo.ca> wrote:

>> Can you elaborate on "leads to R being killed"? You should tell to the killer not to do it again :).
> 
> Hi Simon!
> 
> Sure, but who do you tell it if you don't know the killer?
> This is all the killer left me with, the 'crime scene' if you like :-)
> 
>> m <- matrix(0, 90000, 100000)
> Killed: 9
> 
> My colleague Wayne Oldford also tried it on his Mac machine and
> apparently the killer went further down the hallway to his office
> now... so scary. Here is Wayne's sessionInfo():
> 

Yes, indeed, scary - since it means someone is killing R which means there is not much R itself can do about it. In fact from the syslog I see

May  4 20:48:11 ginaz kernel[0]: low swap: killing pid 56256 (R)

so it's the kernel's own defense mechanism. The bad thing is that R cannot do anything about it - the kernel just decides to snipe processes it thinks are dangerous to the health of the system, and it does so without a warning.

Cheers,
Simon


>> sessionInfo()
> R version 3.2.4 (2016-03-10)
> Platform: x86_64-apple-darwin13.4.0 (64-bit)
> Running under: OS X 10.10.5 (Yosemite)
> 
> locale:
> [1] en_CA.UTF-8/en_CA.UTF-8/en_CA.UTF-8/C/en_CA.UTF-8/en_CA.UTF-8
> 
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
> 
> loaded via a namespace (and not attached):
> [1] rsconnect_0.4.1.11 tools_3.2.4
>> 
> 
> Cheers,
> M
> 
>> 
>> Cheers,
>> Simon
> 



[Rd] R process killed when allocating too large matrix (Mac OS X)
Simon Urbanek