User Tools

Site Tools


interactive_jobs

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Next revision
Previous revision
interactive_jobs [2014/02/16 20:39]
rdiazgar created
interactive_jobs [2014/02/25 17:36] (current)
rdiazgar
Line 7: Line 7:
 </​file>​ </​file>​
  
-It's that easy. Qlogin will create an interactive session attached to the specified queue. You can play around as much as you want as in a normal session. You can also specify all options seen so far for qsub (-l hostname=HNAME,​ -pe openmpi N, -N NAME, etc...).+It's that easy. Qlogin will create an interactive session attached to the specified queue. You can play around as much as you want as in a normal session. You can also specify all options seen so far for qsub (-l hostname=HNAME,​ -pe openmpi N, -N NAME, etc).
  
 Using interactive sessions instead of normal sessions is crucial to ensure the good performance of the cluster. For instance, by specifying the number of CPU/slots that the session will require and a node name, you will prevent other jobs to be assigned to the node in which the interactive session is running. So say that cronus has 64 free slots, and we create an interactive session that will use 12 slots (in which we will run a matlab instance with matlabpool). Then, there will be 52 nodes availables for that node that other jobs will use. Note that if we ran a matlabpool session in a normal terminal, no slots would be reserved and hence 64 other jobs could run in that same node. Using interactive sessions instead of normal sessions is crucial to ensure the good performance of the cluster. For instance, by specifying the number of CPU/slots that the session will require and a node name, you will prevent other jobs to be assigned to the node in which the interactive session is running. So say that cronus has 64 free slots, and we create an interactive session that will use 12 slots (in which we will run a matlab instance with matlabpool). Then, there will be 52 nodes availables for that node that other jobs will use. Note that if we ran a matlabpool session in a normal terminal, no slots would be reserved and hence 64 other jobs could run in that same node.
 +
 +==== Creating an interactive session with more than one slot/CPU ====
 +
 +If we want to create an interactive session that will use more than one CPU, the following example should do the work:
 +
 +<​code>​
 +qlogin -q ttn.q -pe smp 12
 +</​code>​
 +
 +The qlogin statement will create an interactive session in the best available node, requesting 12 CPU's.
  
interactive_jobs.1392611996.txt.gz · Last modified: 2014/02/16 20:39 by rdiazgar