PFRATH specifies the page fault rate above which the limit of a working set is automatically increased. The unit of measure is the number of faults per 10 seconds of processor time. At a setting of 120, for example, the system automatically increases the limit of a working set if it is faulting more than 120 pages per 10 seconds. Decreasing the value of this parameter tends to increase the limits of the working sets, while increasing its value tends to decrease their limits. PFRATH has the AUTOGEN, DYNAMIC, and MAJOR attributes.