Monitoring disk and processor time

The % Disk Time, % Disk Read Time, and % Disk Write Time counters of the Logical Disk object monitor the percentage of time spent servicing the particular I/O requests during the sampling interval. Use the % Disk Time counter in conjunction with the % Processor Time counter of the Processor object to determine the time the system spends executing I/O requests or processing non-idle threads. Use the % Disk Read Time and % Disk Write Time counters to gain further insight into the type of I/O being performed. Your goal is to have a high percentage of time spent executing non-idle threads (high % Processor Time) and executing I/O (high % Disk Time). On a highly optimized system, these counters can be consistently over 90 percent. If one of these counters is substantially lower than the other, it is likely that the high counter indicates a bottleneck, and further investigation is necessary. With high % Disk Time, use the % Disk Read Time and % Disk Write Time counters to get the I/O breakdown. With high % Processor Time, use the % User Time and % Privileged Time to get further CPU utilization breakdown.