title: Crontab process runs very slow
body: <p>I'm trying to run my test script once every hour using crontab that Linux have.</p>
  
  <p>I tested my script before,and it works fine. It takes about 20 mins to finish.</p>
  
  <p>I set everything up with 'crontab -e' and program does start to run. However it runs unreasonably slow. There is one 'cp' command that takes only about 40s to 1 min in shell, but it takes 10 mins in background process. (I check it with 'top')</p>
  
  <p>My script uses threading(3 threads), subprocess and other lib but no sql.
  Also I'm using gmake in the process to build a file, but I can hardly see any builds through 'top'</p>
  
  <p>I tried to debug by using ps -ef | grep python ,find the job ID and us fg job id to get it to the front, but it doesn't work. (Jobs not found)
  This is what shows up in terminal after running for 40 mins(with ps -ef | grep python):</p>
  
  <pre><code>account  11383 11382  0 01:42 ?        00:00:00 /bin/sh -c cd /sirius       /work/account/auto_test/ ; /sirius/tools/bin/python3   /sirius     /work/account/auto_test/revision.py
  account  11384 11383  0 01:42 ?        00:00:00 /sirius/tools         /bin/python3 /sirius/work/account/auto_test/revision.py
  account  12647 11384  0 01:54 ?        00:00:00 /sirius/tools    /bin/python3 /sirius/work/account/auto_test/revision.py
  account  13700  7512  0 02:04 pts/1    00:00:00 grep python
  </code></pre>
  
  <p>I typed in 'jobs -x', nothing shows up </p>
  
  <p>Does anyone know where the problem is or how to speed it up?</p>
  
  <p>I tried with renice -20  but got permission denied</p>
  
  <p>Thanks</p>