Previous Table of Contents Next


OBSERVING NETWORK PERFORMANCE

Once you select one or more counters, you can view the change in the value of those counters over a period of time through the use of the Performance Monitor charting feature. Exhibit 5 illustrates the display of the previously selected Bytes Total/Sec counter in the form of a time chart. In this example, the large solid line near the center of the display represents the present monitoring time and moves from left to right across the display. The display shows that a small burst of network activity occurred, but that there was no continuous high level of network activity that might warrant a network upgrade.

Since the monitoring of just one counter might not indicate other network related problems that can occur without a high level of network utilization being reached, let us return to the “Add to Chart” dialog box so we can note how the values for multiple counters can be simultaneously displayed.


Exhibit 5.  Viewing Network Transmission in the Form of a Line Graph.

Exhibit 6 illustrates the selection of the Connection Session Timeouts counter. This counter can be a valuable indication of poor network performance resulting from a busy file server unable to keep up with client requests. In fact, many times you may wish to select several objects to be plotted over a period of time.

Exhibit 7 illustrates an example of the display of several counters in the form of line charts. Note that different counters can be displayed in different colors on different widths or shapes that can make them easier to view. In addition, you can display multiple objects from the same or from a different computer which provides you with the ability to examine the performance metrics associated with workstations and servers, as well as different network protocols.

Considering the Processor

Although network statistics are important, it is also important to be aware of the performance metrics of a computer’s processor. This is especially true with respect to network servers, as many times, the processing load on a server can result in a degradation of network performance while the network itself is not heavily used. Thus, the ability to examine both network and processor related metrics represents a valuable feature of Windows NT Performance Monitor. To place this capability in perspective, you should note that NetWare’s Monitor utility program only tracks performance of the server and is restricted to displaying statistics concerning server utilization to one server at a time.


Exhibit 6.  Adding the Connection Session Timeouts Counter to the Performance Monitor Chart.


Exhibit 7.  Viewing the Effect of the Selection of Multiple Counters.


Exhibit 8.  Selecting the % Processor Time Counter for the Processor Object.

Exhibit 8 illustrates the selection of the Processor object and the % Processor Time counter for that object. In Exhibit 8, the author again clicked on the Explain button to provide a definition of the Processor Time counter at the bottom of the dialog box. Note that the Processor Time is defined as the percentage of the elapsed time that a processor is busy executing a non-idle thread. This means you can examine the computer bound performance of a processor by displaying the values of this counter. This can be extremely important if you are using a Windows NT platform as a server and want to examine the effect of placing predefined loads on the server. To do so, you could coordinate the predefined operation of a server activity by several employees to examine its effect upon processor utilization. Then, you could extrapolate the percentage of processor utilization per employee to determine how many simultaneous activity requests the processor is capable of supporting. This information may alert you to the fact that you may require a higher performance processor or an additional processor.

For example, if your extrapolation indicated that a Pentium 100 MHz processor was capable of supporting 10 simultaneous activities, and you expect or require the support of 12, you might consider replacing your processor with a 133 MHz or 166 MHz processor.


Exhibit 9.  Selecting the % Processor Time Counter to Generate an Alert.

Working with Alerts

In addition to charting counters, Performance Monitor includes the ability to generate alerts. Alerts enable you to continue working while Performance Monitor tracks predefined events and notifies you when an event threshold is reached.

In a manner similar to charting, you select alerts. First you select an icon or use the View menu “Add to Alert” menu entry to display a dialog box with that label. Exhibit 9 illustrates the Add to Alert dialog box for which the % Processor Time counter was selected for the processor object. Note that this dialog box enables you to specify a threshold for the alert as well as if the alert should be generated when the value of the selected counter is over or under the threshold. In addition, you can specify a program or macro that you want to run whenever the specified alert occurs. If you do not specify a program or macro, you can observe the Performance Monitor Alert log to determine if any alerts occurred and if so, when they occurred, as well as the values of counters being tracked when the alert occurred.

After selecting the % Processor time counter to generate an alert when the percentage of processor use exceeded 50%, the author similarly set an alert for the % User Time counter. Then, the author executed several compute intensive applications on the computer being monitored in an attempt to generate several processor related alerts. The result of this action is shown in Exhibit 10, which illustrates the Performance Monitor alert log. Note that this log indicates the occurrence of two % Processor Time alerts and two % User Time alerts during the monitored period.


Exhibit 10.  Examining the Performance Monitor Alert Log.

RECOMMENDED COURSE OF ACTION

In addition to charting counter values and generating alerts, Performance Monitor can be used to generate a variety of performance related reports. Due to this capability, Performance Monitor provides network administrators and managers with a significant capability to view and track a variety of computer and network related metrics that are extremely valuable when attempting to support a modern client/server environment. By periodically using Performance Monitor, you can use this built-in Windows NT utility program to ensure your network, to include your client/server computing environment, provides the level of support necessary to enhance employee productivity.


Previous Table of Contents Next

Copyright © CRC Press LLC