This counter counts physical disk read I/Os performed to satisfy page faults, tracked within the general System statistics group. This System-group counterpart to the Page group's read-I/O counter lets the admin see paging-driven disk read load in the same summary view as overall CPU and process counts. For example, a spike in this counter coinciding with a rise in the system's overall process count suggests newly-launched processes are driving extra disk reads as they build up their working sets.