[R] How to limit memory on a server

[Prof Brian Ripley]

On 04/10/2012 10:07, Hervy Cyril wrote:
>
> I think R keeps all the data in RAM ? The function memory.limit() refers to the RAM size ?
> I will try to configure the OS.

You are still confused.  No, memory.limit() refers to virtual memory, 
and a process on a tolerably recent OS does not even know if VM is 
mapped or not without using OS-specific system calls (which R does not).

?memory.limit talks about 'obtainable memory', not RAM.

Because Windows manages VM poorly, R for Windows is set up to try to 
keep its VM usage less than an amount that is likely to be mapped at 
once.  But you can alter that, and with a fast SSD it may be worthwhile 
to do so.

It is not even true that 'R keeps all the data in' *memory*: that's the 
point of lazy-loading.  R objects in packages (including most of R 
itself) are kept on disc databases until actually used.

>
> Thanks.
> Best regards
>
> Cyril Hervy
>
>
> -----Message d'origine-----
> De : Prof Brian Ripley [mailto:ripley at stats.ox.ac.uk]
> Envoyé : mercredi 3 octobre 2012 17:22
> À : Hervy Cyril
> Cc : R-help (r-help at r-project.org)
> Objet : Re: [R] How to limit memory on a server
>
> On 03/10/2012 16:12, Hervy Cyril wrote:
>>
>> My OS is a 64-bit Windows Server 2008 SP2 and I would like to limit RAM usage on the server.
>
> Ask your sysadmins, as Duncan Murdoch advised.  R only know about virtual memory usage, not RAM usage.
>
>> Thank you.
>> Best regards
>>
>> Cyril Hervy
>>
>> -----Message d'origine-----
>> De : Prof Brian Ripley [mailto:ripley at stats.ox.ac.uk] Envoyé :
>> mercredi 3 octobre 2012 15:43 À : Hervy Cyril Cc : R-help
>> (r-help at r-project.org) Objet : Re: [R] How to limit memory on a server
>>
>> And your OS is?  See the footer and the 'at a minimum' information the posting guide asks for.
>>
>> I think you are confusing 'memory' and 'RAM': the two concepts are distinct.
>>
>> But R is not a special case, and you do it the same way as you do this for any other process, by your OS facilities.
>>
>> On 03/10/2012 10:12, Hervy Cyril wrote:
>>> Hello,
>>> In our structure, users connect to a server (64GB of memory) where they launch R. How can I limit the amount of RAM that could use a user.
>>> The function memory.limit(size=...) can limit the amount of memory but I would like users can't change this option in R. Is it possible?
>>> Thank you.
>>>
>>> Cyril Hervy
>>>
>>> 	[[alternative HTML version deleted]]
>>>
>>> ______________________________________________
>>> R-help at r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>> PLEASE do read the posting guide
>>> http://www.R-project.org/posting-guide.html
>>> and provide commented, minimal, self-contained, reproducible code.
>>>
>>
>>
>
>


-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
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