Troubleshooting Features

Windows NT 4.0 includes four new troubleshooting features that warn you when Performance Monitor, or its data source, Performance Library, collect uninterpretable data, or when extensible counters threaten the operating system or session.

Tip

Extensible Counter List (Exctrlst.exe), a tool on the Windows NT Resource Kit 4.0 CD in the Performance Tools group (\PerfTool\CntrTool), lists the extensible counters installed on a computer. It can be used on the local or a remote computer. For more information, see Rktools.hlp.

• You can configure Performance Monitor to log warnings and errors to the Windows NT Event Viewer application event log when it fails to retrieve data or receives uninterpretable data. This is highly recommended for frequent users, because the event log is the only clear indicator that Performance Monitor has encountered bad data. Performance Monitor event logging is turned off by default.

• You can also configure the Windows NT Performance Library, the source of Performance Monitor data, to log its errors to the application event log and control the detail of events logged. The default is to log errors only, but if experience trouble with extensible counters, you might want to increase the logging level.
• You can determine how thoroughly Performance Library tests the data buffers returned by extensible counters, and adjust this value based on your estimation of the reliability of your counters. The default is maximum testing.
• Performance Library now times the Open procedure calls of extensible counters and writers an error to the Event Viewer application event log if the call exceeds a time threshold. You can increase the time threshold (the default is five seconds) to prevent unnecessary logging of normal delays, or shorten it to monitor the actual time of the calls.

This section explains each of these features. The troubleshooting features of Performance Monitor reveal the importance of its data source, the Windows NT Performance Library.

The Performance Library is dynamic link library of functions grouped by object. To collect counter data, Performance Monitor calls the Windows NT Registry which requests the data by using Performance Library functions. Performance Library functions request information from the Windows NT Executive, particularly from the Hardware Abstraction Layer (HAL), a platform-specific DLL. The Performance Library associates the system data with each performance object and returns data for each object to Performance Monitor.

When Performance Library fails to retrieve data or encounters data errors or invalid data, these problems become apparent only in Performance Monitor.