OR-Library is a collection of test data sets for a variety of OR problems.
A full list of the test data sets available in OR-Library can be found here.
There is currently 1 data file. This data file contains PASCAL code for generating open shop scheduling problems. It also contains random seeds and lower bounds/upper bounds for a number of different problems of sizes ranging from 4 jobs on 4 machines to 20 jobs on 20 machines. These problems are the problems given in "Benchmarks for basic scheduling problems" by E. Taillard, European Journal of Operational Research, vol.64, no.2, (1993) pp278-285. The data file is called openshop. The file is of size 5Kb (approximately).
Click here to access this file
Other test problems are available here and here