zSERIES CAPACITY MANAGEMENT - A TRUE STORY

摘要

In September 2003, just five months after our previous mainframe upgrade, John Lewis added another two processors to their zSeries machine. Within days the peak hour CPU reached 94%; and we hadn't even reached our peak time of year! Fifteen months later, we are running with the same capacity, and have provided an excellent service in the run up to Christmas 2004, despite an increase of over 25% in business transactions. This paper tells how, by a mixture of good luck and good judgement, John Lewis have moved from reactive panic to controlled and effective capacity management.