[R] Stopping a function execution automatically after a given time

[Prof Brian Ripley]

For information, the R-devel version of R now has an experimental function 
setTimerLimit() to set time limit(s) (elapsed and/or CPU) for each 
top-level function.  It will be a while before (or even if) it is 
released, but it may prove useful to those with an immediate need.


On Wed, 2 Apr 2008, Prof Brian Ripley wrote:

> On Wed, 2 Apr 2008, Duncan Murdoch wrote:
>
>> On 4/2/2008 12:00 PM, Lukas Rode wrote:
>>> Dear Bert and Mel,
>>> 
>>> thanks for your help, but I'm afraid this doesn't solve my problem.
>>> 
>>> As I wrote in my previous mail (cf quote below) in most cases I will not 
>>> be
>>> able to modify the code of the function that I want to run. This is why I
>>> was asking for a wrapper solution similar to what tryCatch does. I have
>>> hinted at a very inelegant version that generates a new R process for each
>>> function run and kills the process after a given time. But I'm sure there
>>> must be something more elegant. I hope I have been clear enough in my
>>> problem description.
>> 
>> On some systems (not Windows) you could ask some external process to
>> send a signal after a certain time interval, and I believe you can write
>> you code to recover afterwards.  I don't know any reasonable way to do
>> this on Windows.
>
> The problem is that only drastic signals will get listened to, and I don't 
> believe they allow you to do anything other than save your work.  SIGKILL, 
> SIGTERM, SIGUSR1 and SIGUSR2 are those likely to work (see ?Signals).
>
> Philippe Grosjean said
>
>> You should look at AutoIt or Autohotkey for this.
>
> I don't see how that helps.  R will not respond to keys when running a 
> function, including the interrrupt key, unless written to do so.  So on 
> Windows if the long-running code is predominantly R (and not compiled C or 
> Fortran) and is running from Rgui or interative Rterm (unlikely) then 
> pressing ESC/Ctrl-C should interrupt fairly soon.
>
> But almost certainly one is using a batch process.  You can kill that from an 
> external process on Windows (but not via SIGUSR1/2, although I think that is 
> a non-implementation detail).
>
>
> I do this by running multiple processes and setting a CPU limit on them from 
> the shell used to launch them.  By using 'make -j' I can control how many run 
> at once (important on multi-CPU machines).
>
>
>> 
>> Duncan Murdoch
>> 
>>> 
>>> Thanks again,
>>>   Lukas
>>> 
>>> Here is what I wrote before:
>>> Note that mostly these functions are not written by me and not R code 
>>> (like
>>> nlme for example), so it is not feasible to adapt the function itself.
>>> Rather, it needs to be a wrapper around the function, similar to tryCatch.
>>> 
>>> 
>>> 
>>> On Wed, Apr 2, 2008 at 5:23 PM, mel <mel at altk.com> wrote:
>>> 
>>>> Lukas Rode a écrit :
>>>> 
>>>>> Nowever, with regard to #2, I am lost. I would like to set a maximum
>>>> time
>>>>> limit (say, 1 minute) and if my procedure is still running then, I would
>>>>> like to move on to the next model.
>>>> 
>>>> 
>>>> begin_time = as.difftime(format(Sys.time(), '%H:%M:%S'), units='secs');
>>>> for(...)
>>>>  {
>>>>  ...
>>>>  current_time = as.difftime(format(Sys.time(), '%H:%M:%S'), 
>>>> units='secs');
>>>>  delay = current_time - begin_time;
>>>>  if (delay>60) return();
>>>>  }
>>>> 
>>>> a counter may also be enough
>>>> 
>>>> ______________________________________________
>>>> 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.
>>>> 
>>>
>>> 	[[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.
>> 
>> ______________________________________________
>> 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)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595

-- 
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)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595