It is important for a technician to understand how a computer is performing and be able to analyze why a computer might be running slow. In order to do that, a technician must know what type of applications are being run on the computer and what are the effect of these applications on the computer resources. A technician must also be able to monitor the computer's resource usage whenever problems occur, change the configuration as needed, and observe the results of the configuration change.

Three utilities are commonly used to monitor system performance: Task Manager, Performance tool's System Monitor, and Performance tool's Performance Logs and Alerts. Task Manager is used to monitor your system's current performance. System Monitor is used to monitor real-time data about specific computer components. Performance Logs and Alerts allows you to create logs about the computer's performance and create alerts that notify you when a specific instance being monitored reaches a threshold that you define. It includes a summary graph of processor and memory usage.

Task Manager has been discussed in previous section. How to use it to monitor your computer's performance is as follows: Access Task Manager and click on the Performance tab. Task Manager immediately starts gathering CPU and memory usage statistics and displays them in graph form in the window. Figure XP-8 shows the Task Manager graphs.

The first window on the left, CPU Usage, shows the CPU usage percentage or what percentage of time the processor is working. Actually, it is a percentage of time the processor is running a thread. A thread is a type of Windows object that runs application instructions. The first window on the right, CPU Usage History, is a graph of how busy the microprocessor has been over a period of time.

The second window on the left (PF Usage) shows the amount of virtual memory (the paging file) being used. The amount shown is in megabytes as evidenced by the M after the number. If the display shows that the paging file is near the maximum, you can adjust the page file size. The following steps allow you to set the paging file size:
1. Click on the S'tart button and select Control Panel.

2. If in category view, select Performance and Maintenance followed by the System control panel icon. If in classic control panel view, double-click on the System control panel icon.

3. Click on the Advanced tab, locate the Performance section, and click on the Settings button.

4. Click on the Advanced tab, locate the Virtual Memory section, and click on the Change button. The second window on the right, Page File Usage History, is a graph of the virtual memory used over time. Memory is a frequent bottleneck for computer performance issues. Task Manager can also be used to see the total amount of RAM installed and how much RAM is available. Look in the Physical Memory information section in the Task Manager window to see this.