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Center for High Throughput Computing

Access More Capacity on Computers With New Linux Version (HTC System)

The HTC System is Transitioning to a Newer Linux Version (CentOS 7)

CHTC staff are in the midst up upgrading the default operating system on our high throughput compute system from Scientific Linux 6 (SL6) to a newer and slightly different Linux version - CentOS 7. We will update this page with more information as we pass major transition milestones.

To access the full capacity of CHTC high throughput computing, submit your jobs to run on both the old and new operating systems. See the instructions below.

1. Current Status

We have started converting our computers to the new operating system, in a gradual process over the course of the next several months. As of June 15, about 25% of our HTC system is running CentOS 7, and we will increase it as YOU submit more jobs that fill up the CentOS 7 job slots!

2. Who Can Use CentOS 7?

At this point, all users of our HTC system are encouraged to start transitioning their computational work to run on our two operating systems, in order to get the maximum possible amount of computing. See the section below for important details on testing your jobs and then using either or both operating systems.

3. Getting Started on CentOS 7

A. Run a Test Job

First, submit 1-5 jobs that are typical for your work, after adding the following line to your submit file:

requirements = (OpSysMajorVer == 7)

If the test jobs complete successfully, you are ready to run on CentOS 7. If you see errors or failed jobs, please contact the CHTC facilitators as we want to know what doesn't work.

B. Running Real Jobs

By default, jobs will still run only on Scientific Linux 6. You must opt into using CentOS 7 by adding requirements to your submit file. Once you've run a test job and are ready to run on both operating systems (or just CentOS7), do the following:

Option 1: To run jobs on both SL6 and CentOS 7

This is the option you should use if you want to access as many computers as possible. Add the following line to your submit file:

requirements = (OpSysMajorVer == 6) || (OpSysMajorVer == 7)
Option 2: To run jobs on only CentOS 7

You should only choose this option if your code needs something specific from the newer operating system and won't run successfully on SL6. Add the following line to your submit file:

requirements = (OpSysMajorVer == 7)


Combining Requirements

Does your job already have a requirements statement? If so, you can add the requirements above to the pre-existing requirements by using the characters &&. For example, if your jobs already require Gluster:

requirements = (Target.HasGluster == true) 
You can add the requirements for using both operating systems like so:
requirements = (Target.HasGluster == true) && ((OpSysMajorVer == 6) || (OpSysMajorVer == 7))