[R] socket clusters on snow dies easily

[Rong-En Fan]

hello,

  I'm using R 1.8.1 with the lastest snow package on FreeBSD 4.9.
  However, when I try to using socket clusters, it's very unstable.
  Sometimes it dies half way when I run parSapply(), sometimes
  it dies when cluster connection is idle.

  I create a socket cluster by following cmd

  cl = makeCluster("foo", type = "SOCK", outfile="/tmp/rafanlog");

  Then, I just idle in R, and tail -f outfile, I got following:

  [... some R msgs ...]

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for a HTML browser interface to help.
Type 'q()' to quit R.


>
> #library(serialize)
> library(snow)
>
> slaveLoop(makeSOCKmaster())
Error in unserialize(node$con) : error reading from connection
Execution halted


  after makeCluster() returns, the outfile hangs around the empty lines
  above, about 1 minute later, all msg shows up, also it dies.

  This is reproducible on my machine. Also, one of my friends also 
  got this result on Linux machines w/ R 1.8.x.

  Is there any one also encounter this problem?
  Any comments or suggestion are welcome :)

Regards,
Rong-En Fan