[R] help wanted using R in a classroom

[Don MacQueen]

Re-reading your email carefully, I'm not absolutely sure whether the 
multiple R processes are all running on the server, as I first 
assumed. If they are, then it seems to me that the solution is to get 
the R processes running on the clients.

On my OS X box, "R" is a link to the R script located on an NFS 
mounted file system:

[166]% ls -l /usr/local/bin/R
lrwxr-xr-x  1 root  wheel  42  9 Dec 12:25 /usr/local/bin/R@ -> 
/statsrvr/apps/R/R-2.0.1/darwin/bin/R

[167]% df -k | grep statsrvr
statbox:/APPS1               9830344  9161202    659312    93% 
/private/automount/statsrvr/apps

statbox is a Solaris machine.

So, R is "installed", by which I mean all of its files are located 
on, a server, but when I run it, it runs locally.

So I think should be able to arrange things so that each student's R 
session runs on the eMac in front of him, instead of on the server.

-Don

At 12:11 PM +0100 1/17/05, Sam Parvaneh wrote:
>Hi everyone!
>
>I'm using R 2.0.1 for Mac OS X in a classroom with 40 eMacs running Mac OS
>X version 10.3.6.
>These Macs are network based, meaning that the students log in to an
>XServe G4 where their user accounts and home directories are stored.

Do they actually log in to the XServe, or do they login to the eMac 
and have their home directories mounted on the eMac?

>
>The problem that I'm having each time a group of students (usually 7 to
>10) use R is that the whole system get incredibly slow.
>The response time for opening an application  while the students are
>running R is around 5 minutes.
>If a student wants to log into the system while others are running R, it
>can take up to 10 minutes for the student to get logged in.
>Everything gets very slow that it's almost impossible to work.
>When I look at the server Graphs, the CPU usage of the first CPU is always
>100% when these students are using R. The second CPU is left at 15%.
>
>When these students quit R, then everything's is back to normal again. The
>usage of both CPUs go back down to between 5-10%.
>Is there anyone out there using R in a university like this?
>Does anyone have an idea what this might depend one or maybe a solution?
>I can provide some more information if anyone wants, if you think you can
>help me.
>
>Thanks in advance
>/Sam
>
>
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>
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-- 
--------------------------------------
Don MacQueen
Environmental Protection Department
Lawrence Livermore National Laboratory
Livermore, CA, USA