For a lot of organizations that buy servers and create systems out of them, the overall throughput of each single machine is the most important performance metric they care about. But for a lot of IBM i shops and indeed even System z mainframe shops, the performance of a single core is the most important metric because most IBM i customers do not have very many cores at all. Some have only one, others have two, three, or four, and most do not have more than that although there are some very large Power Systems running IBM i. But that is on the order of thousands of customers against a base of 120,000 unique customers.

We are, therefore, particularly interested in how the performance of the future Power10 processors will stack up against the prior generations of Power processors at the single core level. It is hard to figure this out with any precision, but in its presentation in August at the Hot Chips conference, Big Blue gave us some clues that help us make a pretty good estimate of where the Power10 socket performance will be and we can work backwards from there to get a sense of where the Power10 cores could end up in terms of the Commercial Performance Workload (CPW) benchmark ratings that IBM uses to gauge the relative performance of IBM i systems.