Page Faults/sec is overall rate at which of faulted pages are handled by the processor. It is measured in numbers of pages faulted. A page fault occurs when a process requires code or data that is not in its working set (its space in physical memory) in main memory. This counter includes both hard faults (those that require disk access) and soft faults (where the faulted page is found elsewhere in physical memory.) Most processors can handle large numbers of soft faults without consequence. However, hard faults can cause significant delays.