Grid Jobs

The cluster is set up to process jobs submitted via the grid. For more about what the grid is visit http://www.gridpp.ac.uk/explain.html, while this site is specific to particle physics other areas of science also have grid initiatives, e.g. biomed, neiss, which are supported by the htc cluster.

In order to submit a grid job you need a grid certificate and access to a computer that is runing the User Interface (UI) middleware

Example

First create a file which contains the Job Description Language commands to run the job, say helloworld.jdl. The Virtual Organisation (VO) in my case is altas,

#############Hello World#################
Executable = "/bin/echo";
Arguments = "Hello welcome to the Grid ";
StdOutput = "hello.out";
StdError = "hello.err";
OutputSandbox = {"hello.out","hello.err"};
VirtualOrganisation = "atlas";
#########################################

The Executable is the execuatable you want to run (normally a script but in this case just a simple command), Arguments are any arguments you wish to give to the comman/script. The Input Sandbox is a list of files that you want to send with the job and the Output Sandbox is the list of files you want to retrieve when it has finished.

Now make a temporary version of your Grid Certificate (you need to do this once every session or after 12 hours have elapsed):

[sim@gridsub ~] voms-proxy-init --voms atlas

Now submit the job:

[sim@gridsub ~] glite-wms-job-submit -a -o jobIDfile helloworld.jdl

You can find out the status by typing:

[sim@gridsub ~] glite-wms-job-status -i jobIDfile

Once the job has terminated you can retrieve the output (jo is the directory to save the job output):

[sim@gridsub ~] glite-wms-job-output -i jobIDfile --dir jo