HOWTO: Use Jupyter on OnDemand
This page outlines how to use the Jupyter interactive app on OnDemand.
Launching Jupyter App
Log on to https://ondemand.osc.edu/ with your OSC credentials. Choose Jupyter under the InteractiveApps option. 
Training
HOWTO: Run Python in Parallel
We can improve performace of python calculation by running python in parallel. In this turtorial we will be making use of the multithreading library to run python code in parallel.
HOWTO: Use a Conda/Virtual Environment With Jupyter
The IPython kernel for a Conda/virtual environment must be installed on Jupyter prior to use. This tutorial will walk you though the installation and setup procedure.
HOWTO: Use Extensions with JupyterLab
JupyterLab stores the main build of JupyterLab with associated data, including extensions in Application Directory. The default Application Directory is the JupyterLab installation directory where is read-only for OSC users. Unlike Jupyter Notebook, JupyterLab cannot accommodate multiple paths for extensions management. Therefore we set the user's home directory for Application Directory so as to allow user to manage extensions.
HOWTO: Tune VASP Memory Usage
This article discusses memory tuning strategies for VASP.
Data Distribution
Typically the first approach for memory sensitive VASP issues is to tweak the data distribution (via NCORE or NPAR). The information at https://www.vasp.at/wiki/index.php/NPAR covers a variety of machines. OSC has fast communications via Infiniband.
HOWTO: Debugging Tips
This article focuses on debugging strategies for C/C++ codes, but many are applicable to other languages as well.
Rubber Duck Debugging
This approach is a great starting point. Say you have written some code, and it does not do what you expect it to do. You have stared at it for a few minutes, but you cannot seem to spot the problem.
HOW TO: Look at requested time accuracy using XDMoD
The XDMoD tool at xdmod.osc.edu can be used to get an overview of how accurate the requested time of jobs are with the elapsed time of jobs.
To request an amount of time for a job, you can use the following header.
#SBATCH --time=xx:xx:xx
The elapsed time is how long the job ran for before completing. This can be obtained for completed jobs using the sacct command.
HOWTO: Collect performance data for your program
This page outlines ways to generate and view performance data for your program using tools available at OSC.
Intel Tools
This section describes how to use performance tools from Intel. Make sure that you have an Intel module loaded to use these tools.
Intel VTune
Intel VTune is a tool to generate profile data for your application. Generating profile data with Intel VTune typically involves three steps:
UNIX Basics
OSC HPC resources use an operating system called "Linux", which is a UNIX-based operating system, first released on 5 October 1991. Linux is by a wide margin the most popular operating system choice for supercomputing, with over 90% of the Top 500 list running some variant of it. In fact, many common devices run Linux variant operating systems, including game consoles, tablets, routers, and even Android-based smartphones.
