title: R parallel computing by doSNOW package, processes registered but not consuming CPU cores
body: <p>I am using the doSNOW package on my desktop. </p>
  
  <pre><code>cl &lt;- makeCluster(6, type="SOCK")
  registerDoSNOW(cl)
  m &lt;- matrix(rnorm(90000), 30000, 3)
  foreach(i=1:nrow(m), .combine=rbind) %dopar% (m[i,] / mean(m[i,]))
  stopCluster(cl)
  </code></pre>
  
  <p>When the above program is running, I opened the Window Task Manager, and in the Processes tab I saw there are 5 or 6 new-created processes named "Rscript.exe", but only one of them is running. </p>
  
  <p>I am using my office desktop. I remember the first time I used "doSNOW" on my own laptop, Windows popped out a small dialogue bar asking some kind of permission, but my office desktop never asked me that. I don't know if my situation has something to do with some system block, just a note here.</p>
  
  <p>Many thanks in advance to whom can help me.</p>
  
  <p>Sincerely
  Charlie</p>