Please let us know if you no longer require your HPC account or if you have acknowledged the use of the UCTHPC cluster in any publications recently. We rely on acknowledgements in order to motivate for new equipment.
Processes on the head node:
By agreeing to the Acceptable Usage Policy you confirm that all work will be carried out on the worker nodes, not the head node. This includes such activities as un\compressing data with tar or zip. Small amounts of work that take only a few seconds are fine, however running zip or unzip for an hour directly on the head node is not acceptable. Starting an interactive job on the cluster is quick and easy, see below.
Interactive jobs:
There is a new interactive job wrapper. You can now run sintx, instead of sint to start an interactive job. If you only have access to one partition and need only a single core then running sintx with no arguments starts a new job immediately as long as there are free cores. If you have been granted access to more than one partition then you will have to specify the partition name. If you require more than one core for your interactive job then add the –ntasks=4 argument for example. In addition sintx sets up the DISPLAY environment variable automatically allowing you to export graphical displays to your desktop. The older wrapper, sint, is still available.
Example: user@hpc ~$ sintx Starting interactive job exporting DISPLAY to :137.158.123.1 user@srvcnthpc126 ~$ _ ... user@srvcnthpc126 ~$ exit (when done)
Matlab:
The latest version of Matlab has been installed on the cluster, R2021B. To activate it type:
module load software/matlab-R2021b
New GPU cards:
We recently installed 8 Nvidia A100 cards. This was funded by several research groups as well as ICTS. The ICTS portion has been donated to the general pool of researchers and is available on request. You can read more about this here.
DASK (Parallel Python):
We have created a new Python module which incorporates DASK. This allows one to scale Python jobs in true parallel fashion on the cluster. If you are using Numpy, Pandas, joblib, scikit etc this has the potential to greatly speed up your jobs but does come with a significant learning curve.
Training:
Online training courses can be arranged in Teams or Zoom. The number of participants is limited to four at a time.
VPN:
The UCT VPN was updated some months back. The maximum length of a VPN session is 12 hours. If you are running long term interactive jobs you should make use of the screen function. Given the amount of load shedding that is occurring at the moment the use of screen could save you a great deal of inconvenience.