OLCF Test Harness version 2.1

This release of the OLCF Test Harness (OTH) includes extensive code restructuring from the original NCCS Test Harness released in 2016.

Highlights of main features introduced:

INI configuration file for each machine
INI configuration file for each test
Build, submit, and check driver scripts are now included within the OTH driver rather than required per test
Support for LSF, SLURM, and PBS schedulers