Abstract: Techniques for accounting microprocessor resource consumption. The present invention provides an automatic method to timely determine the current microprocessor clock frequency. Information provided by timer facilities of the microprocessor is reused by sampling this information at constant intervals. Such direct derivation of the microprocessor clock frequency is a real-time method that also takes into consideration secondary effects. Examples for such secondary effects include clock frequency variations across chips due to manufacturing variations, any degradation due to performance loss by thermal, or other detrimental effects as well as any voltage changes. In the preferred embodiment of the invention, the real-time microprocessor clock frequency determination is implemented as part of the microprocessor itself. No additional service processors or other external hardware facilities are needed in order to control the microprocessor clock frequency determination function.

Abstract: Redundant time-of-day (TOD) oscillators are aligned, within a master oscillator path, to local logic oscillator and used to create independent step-sync signals. A step checker validates and provides selection signals to identify which of the TOD oscillators operates according to a criterion. Independent step-sync signals are transmitted to several sibling chips. Local step and sync signals are delayed to arrive at TOD register nearly synchronous with TOD registers in sibling chips. A slave oscillator path may be used to select time signals generated in a sibling chip, whereby the master oscillator path is deselected. A primary control register set may be used to configure which among several chips is a master chip using the master oscillator path. All remaining chips are slave chips. All segments of the topology are redundant. One of multiple possible alternate topologies is defined in a secondary control register set.