R help - Sep 2004 - Is there any way to release memory in running time?

Hi all,

I am doing some intensive computation right now. My system is Pentium4 3.20G 
+ 1.0G RAM + WindowsXP + R1.9.1. It seems my computer is very powerful. 
However, when I do some simple matrix algebra operations based on a matrix 
(DD) with dimension 5000000 by 2, I found that the consumption of RAM is 
huge. For example, the command a <- 1 - DD[,2] eats my 100M RAM. Does anyone 
know how to release memory in the middle of program (running time)? BTW, the 
command rm() does not free memory unless you quit R as I as know. Thanks in 
advance.

Rui

See ?gc.

Sean

On Sep 30, 2004, at 12:52 PM, <wanr at ucalgary.ca> wrote:
> Hi all,
>
> I am doing some intensive computation right now. My system is Pentium4 
> 3.20G
> + 1.0G RAM + WindowsXP + R1.9.1. It seems my computer is very powerful.
> However, when I do some simple matrix algebra operations based on a 
> matrix
> (DD) with dimension 5000000 by 2, I found that the consumption of RAM 
> is
> huge. For example, the command a <- 1 - DD[,2] eats my 100M RAM. Does 
> anyone
> know how to release memory in the middle of program (running time)? 
> BTW, the
> command rm() does not free memory unless you quit R as I as know. 
> Thanks in
> advance.
>
> Rui
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide! 
> http://www.R-project.org/posting-guide.html

?gc
/E
wanr at ucalgary.ca wrote:
>Hi all,
>
>I am doing some intensive computation right now. My system is Pentium4 3.20G
>+ 1.0G RAM + WindowsXP + R1.9.1. It seems my computer is very powerful. 
>However, when I do some simple matrix algebra operations based on a matrix 
>(DD) with dimension 5000000 by 2, I found that the consumption of RAM is 
>huge. For example, the command a <- 1 - DD[,2] eats my 100M RAM. Does
anyone
>know how to release memory in the middle of program (running time)? BTW, the
>command rm() does not free memory unless you quit R as I as know. Thanks in 
>advance.
>
>Rui
>
>______________________________________________
>R-help at stat.math.ethz.ch mailing list
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html
>
>  
>

-- 
Dipl. bio-chem. Witold Eryk Wolski         
MPI-Moleculare Genetic
Ihnestrasse 63-73 14195 Berlin           _
tel: 0049-30-83875219                   'v'
http://www.molgen.mpg.de/~wolski       /   \
mail: witek96 at users.sourceforge.net  ---W-W----
      wolski at molgen.mpg.de

I'm not sure I understand your problem.  Your `DD' matrix should 
occupy ~75MB of memory and your `a' vector should occupy ~38MB of 
memory.  That adds up to over 100MB as far as I can see.

As far as I know, there is no way to explicitly give memory back to 
the *operating system*, if that's what you need.

-roger

wanr at ucalgary.ca wrote:
> Hi all,
> 
> I am doing some intensive computation right now. My system is Pentium4
3.20G
> + 1.0G RAM + WindowsXP + R1.9.1. It seems my computer is very powerful. 
> However, when I do some simple matrix algebra operations based on a matrix 
> (DD) with dimension 5000000 by 2, I found that the consumption of RAM is 
> huge. For example, the command a <- 1 - DD[,2] eats my 100M RAM. Does
anyone
> know how to release memory in the middle of program (running time)? BTW,
the
> command rm() does not free memory unless you quit R as I as know. Thanks in
> advance.
> 
> Rui
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html
>