Monitoring and Tuning Your Server

Using PerfMon to Monitor Processor Activity

To monitor your server’s processors, use PerfMon to log data from the counters listed in Table 5.4:

Table 5.4 Counters for Processor Activity Monitoring

Counter	Indicates
System\ Processor Queue Length	Threads waiting for processor time. If this value exceeds 2 for a sustained period of time, the processor may be bottlenecked.
Processor\ % Processor Time (Total instance)	The sum of processor use on each processor.
Processor\ % Processor Time	Processor use on each processor (#0, #1, and so on). In a multiprocessor server, this counter reveals unequal distribution of processor load.
Processor\ % Privileged Time	Proportion of the processor’s time spent in privileged mode. In the Windows 2000 operating system, only privileged mode code has direct access to hardware and to all memory in the system. The Windows 2000 Executive runs in privileged mode. Application threads can be switched to privileged mode to run operating system services.
Processor\ % User Time	Proportion of the processor’s time spent in user mode. User mode is the processor mode in which applications like IIS 5.0 services run.
Process\ % Processor Time	The processor use attributable to each processor, either for a particular process or for the total for all processes. (These are shown in the list of instances.)

False Indications

A memory bottleneck can sometimes look like a processor or disk bottleneck. If the system does not have enough physical memory to store the code and data that are needed, the processor spends substantial time paging. Before adding or upgrading processors or disks, you should monitor the memory in your server. For more information about monitoring memory, see Memory.