Release 10.1A: OpenEdge Getting Started:
Database Essentials

Understanding idle time

Idle time can be positive because it means that the CPUs have capacity to support growth. It is not necessary for idle time to be always greater than zero. If idle time is zero for prolonged periods and there is no significant amount of time logged to wait, you must look deeper into CPU activity to determine the correct course of action.

For example, look at the CPU queue depths. CPU queue depth is the number of processes waiting to use the CPU. If there are always several processes in the queue, you must either:

Increase CPU capacity or increase CPU efficiency.
Reduce demand by fixing code or moving processing to slow periods of the day.

If wait for I/O is high and there is no idle time, you need to increase disk efficiency, reduce I/O throughput, or modify your processing schedule. If wait for I/O is 10 percent or less and you still have idle time, you do not need to urgently work on the problem. You might want to look at those items outlined in the previous paragraph, but there might be nothing you can do to resolve the issue.