Measuring Processor Use

To investigate a processor bottleneck, log the System, Processor, Process, Thread, Logical Disk, and Memory counters for at least several days at an update interval of 60 seconds. Include a network counter if you suspect that network traffic might be interrupting the processor too frequently. The longer you can log, the more accurate your results will be. Processor use might be a problem only at certain times of the day, week or month, and you are likely to see these patterns if you log for a longer duration.

You can use At.exe or Microsoft Test to start and stop Performance Monitor at critical times and batch the logs for later examination.

• At.exe is included in Windows NT workstation and server. For instructions, open a command prompt window and, at the command line, type at /?.

• Microsoft Test is purchased separately. It is described in Chapter 11, "Performance Monitoring Tools."

You can also use CPU Stress to measure the response of your configuration to high processor use and to simulate processor bottlenecks. CPU Stress is a testing tool included on the Windows NT Resource Kit 4.0 CD in the Performance Tools group in \Perftool\Meastool\CpuStres.exe. For more information, see Rktools.hlp.

Performance Monitor includes some direct and some indirect indicators of processor use, for both single- and multiple-processor computers. This section discusses some characteristics of the measurements that you need to know to correctly interpret the values.