Minumum memory requirements to run R.

Quite a while back we set the goal of running R in 16Mb RAM, as people (I 
think Kjetil) had teaching labs that small.

Since then R has grown, and we has recently started to optimize R for 
speed rather than size.  I recently tested R-devel on my ancient Win98 
notebook with 64Mb RAM -- it ran but startup was rather slow on what I 
think is a 233MHz processor and very slow disc.

R still runs in 16Mb, but that is getting tight.  Does anyone have any 
need to run on a smaller machine than my 64Mb notebook?

Prof Brian Ripley wrote:

Quite a while back we set the goal of running R in 16Mb RAM, as people (I 
think Kjetil) had teaching labs that small.

It's a while since I actually har R used on such small machines, I think
64 MB is quite acceptable now.

Kjetil

Since then R has grown, and we has recently started to optimize R for 
speed rather than size.  I recently tested R-devel on my ancient Win98 
notebook with 64Mb RAM -- it ran but startup was rather slow on what I 
think is a 233MHz processor and very slow disc.

R still runs in 16Mb, but that is getting tight.  Does anyone have any 
need to run on a smaller machine than my 64Mb notebook?

Kjetil Brinchmann Halvorsen wrote:

Prof Brian Ripley wrote:

Quite a while back we set the goal of running R in 16Mb RAM, as people (I 
think Kjetil) had teaching labs that small.

It's a while since I actually har R used on such small machines, I think
64 MB is quite acceptable now.

May I add another note to this - I recently upgraded to 64-bits (AMD opteron) 
and noticed the memory foot print of R has shot up. Just starting R takes up 
90+MB virtual.

There are correponding increases with Python and Perl as well; 
I suspect R suffers a bit on 64-bit
platform due to extensive use of pointers internally. The fundamental
unit in R, SEXP, is 6 pointers + 1 int, (and another
pointer for itself). So I would probably say 64MB is questionable on 64-bit, 
but then probably nobody is stupid enough to do that...

That's a different question.  I said RAM, you quote virtual.  I am 
suprised at your figure though, as I am used to seeing 40-50Mb virtual 
at startup on an Opteron.

The distinction is important: even those small Windows machines had 100s 
of Mb of virtual memory available, it was RAM that was in short supply.

There are correponding increases with Python and Perl as well; I 
suspect R suffers a bit on 64-bit
platform due to extensive use of pointers internally. The fundamental
unit in R, SEXP, is 6 pointers + 1 int, (and another
pointer for itself). So I would probably say 64MB is questionable on 
64-bit, but then probably nobody is stupid enough to do that...

We know: we even document it in the appropriate places.

Some of us were running 64-bit R last century on machines with 128Mb 
(and others with much more, of course).  When I tried in 1997, Solaris 
would not run in 64-bit mode with 64Mb RAM (which then cost ?1000 or so).

Prof Brian Ripley wrote:

We know: we even document it in the appropriate places.

I went and have a look - it is the last section of R-admin (and of
course, for those who "read the source", R/include/Rinternals.h). It
would be good to mention this in the FAQ (which it doesn't, or maybe I
didn't look hard enough), or the beginning of R-admin?

On Mon, 23 Jan 2006, Hin-Tak Leung wrote:

Prof Brian Ripley wrote:

We know: we even document it in the appropriate places.

I went and have a look - it is the last section of R-admin (and of
course, for those who "read the source", R/include/Rinternals.h). It
would be good to mention this in the FAQ (which it doesn't, or maybe I
didn't look hard enough), or the beginning of R-admin?

It's not in the FAQ because it isn't a FAQ (yet).

If you use the PDF manual it is in the table of contents on page i.

In the HTML manual it is admittedly less clear: there isn't a table of 
contents and there is nothing obvious in the index. To some extent this is a 
problem with all the manuals. The structure in the .texi file isn't 
translated well to HTML form by the makeinfo tools.

[About Ncell sizes on 64-bit platforms.]

In my build there is a chapter in the HTML manual

    Choosing between 32- and 64-bit builds

in the top-level contents, and the information is in there.

It is also in ?Memory (a fairly obvious place).  It may be elsewhere, 
but those are the most obvious places to me.

The 32-bit/64-bit issue affects purchasing or upgrading decisions
- whether one wants to spend the money on buying cheaper
32-bit machines, versus more expensive 64-bit machines. That
decision would be based on information available while *not* having
an operational R installation...