benchmark data set for Metareasoning problem
In this sort of situation, two standard answers are:


Figure out what the practical applications of your algorithm are.  Find a dataset associated with that particular application, and try your algorithm on it and see how well it works.  Measure success using some metric that is appropriate for that particular application.
Look through the research literature to find previously published papers that try to solve the same problem.  Look at what benchmarks they used.  Use the same benchmarks, so that you can compare how well your algorithm does to previously published algorithms.