[R] Problems with snow and rpvm

[Vittorio]

Dear Friends,
 
I'm trying to learn to use parallel computation using 
snow & rpvm
Now, I have two boxes:
1) Pentium 4, pvm 3.4.5,  R 2.2.0 
with FreeBSD 5.4 (box uffbsd);
2) PowerPC, pvm 3.4.5, R 2.1.1 with 
Debian Linux latest stable (box powerpclinux);

I'm using the 
instructions in (found in snow.pdf) http://www.stat.uiowa.
edu/~luke/R/cluster/cluster.html.

Now ** from the box uffbsd ** using 
some of the example binaries boxed with pvm it seems that all works ok:
.....................................
.....................................
pvm> conf
conf
2 hosts, 2 data 
formats
                    HOST     DTID     ARCH   SPEED       DSIG
             	  uffbsd    40000  FREEBSD    1000 0x00408841
            
powerpclinux    80000 LINUXPPC    1000 0x0658eb59
pvm> mstat 
powerpclinux
mstat powerpclinux
            powerpclinux  ok

pvm> 
mstat uffbsd
mstat uffbsd
             uffbsd  ok

pvm> spawn -> hello
spawn -> hello
[13]
1 successful
t80012
pvm> [13:t80012] i'm t80012
[13:
t80012] from t80013: hello, world from powerpclinux
[13:t80013] EOF
[13:
t80012] EOF
[13] finished

pvm>  spawn -> master1
 spawn -> master1
[11]
1 successful
t8000e
pvm> [11:t40013] EOF
[11:t40014] EOF
[11:
t80011] EOF
[11:t40012] EOF
[11:t80010] EOF
[11:t8000f] EOF
[11:t8000e] 
Spawning 6 worker tasks ... SUCCESSFUL
[11:t8000e] I got 100.000000 
from 1; (expecting 100.000000)
[11:t8000e] I got 300.000000 from 2; 
(expecting 300.000000)
[11:t8000e] I got 500.000000 from 3; (expecting 
500.000000)
[11:t8000e] I got 500.000000 from 0; (expecting 500.000000)
[11:t8000e] I got 700.000000 from 4; (expecting 700.000000)
[11:t8000e] 
I got 900.000000 from 5; (expecting 900.000000)
[11:t8000e] EOF
[11] 
finished

pvm> spawn -> master1
spawn -> master1
[10]
1 successful
t4000e
pvm> [10:t40011] EOF
[10:t40010] EOF
[10:t4000f] EOF
[10:t8000d] 
EOF
[10:t4000e] Spawning 6 worker tasks ... SUCCESSFUL
[10:t4000e] I 
got 700.000000 from 4; (expecting 700.000000)
[10:t4000e] I got 
900.000000 from 5; (expecting 900.000000)
[10:t4000e] I got 500.000000 
from 3; (expecting 500.000000)
[10:t4000e] I got 300.000000 from 2; 
(expecting 300.000000)
[10:t4000e] I got 500.000000 from 0; (expecting 
500.000000)
[10:t4000e] I got 100.000000 from 1; (expecting 100.000000)
[10:t4000e] EOF
[10:t8000c] EOF
[10:t8000b] EOF
[10] finished

pvm> 
spawn -> slave1
spawn -> slave1
[17]
1 successful
t40019
pvm> spawn -> 
slave1
spawn -> slave1
[18]
1 successful
t80017
.........................................
.........................................


Now, starting R ** always 
from box uffbsd **

I get the following
........................
> 
library(snow)
> cl <- makeCluster(2)
Loading required package: rpvm
> 
cl
[[1]]
$tid
[1] 262171
$RECVTAG
[1] 33
$SENDTAG
[1] 22
attr(,"class")
[1] "PVMnode"

[[2]]
$tid
[1] 524312
$RECVTAG
[1] 33
$SENDTAG
[1] 22
attr(,"class")
[1] "PVMnode"
attr(,"class")
[1] "PVMcluster"
......................

But trying any of the commands suggested in the 
cited website such as:

> clusterCall(cl, function() Sys.info()[c
("nodename","machine")])
> clusterEvalQ(cl, library(boot))
> 
clusterApply(cl, 1:2, get("+"), 3)

R invariably freezes and 
frustatrated I have to close the terminal session and restart it all 
over again (to no avail, of course).

The other hint for you could be 
that if - instead of a debian powerpc box - I use a second freebsd box 
with the same software as uffbsd it all works smoothly.

What do you 
suggest to check?

Ciao
Vittorio