The column labeled “Baseline Performance” indicates the percentage of single core performance of the underlying physical CPU allocated to the instance. For example, a t2.small instance has access to 20% of a single core of an Intel Xeon processor running at 2.5 GHz (up to 3.3 GHz in Turbo mode). A t2.medium has access to 40% of the performance of a single core, which you (or your operating system,