The long-standing usefulness of the Task Manager as a tool for "checking under the hood" at what is actually happening with processes and multiple processor usage (in the case of multiprocessor workstations and servers), CPU time taken by task, memory usage, and priorities of tasks has been proven over time. The shortcut access to the Task Manager from the Taskbar also makes this a useful tool in its convenience and succinctness of data presentation.
Right-clicking on the Taskbar presents a pop-up menu that includes Task Manager as the second entry from the bottom. Selecting Task Manager... provides the graphical interface, as shown in Figure 1. Notice that along the top of the Task Manager window there are tabs for Applications, Processes, Performance, Networking, and Users. Microsoft decided to add the last two in Windows XP due to customer requests for greater visibility into networking and user-specific attributes.
Figure 1 The Task Manager interface provides a quick glimpse of how applications and memory are functioning.
What you'll notice as you go through the tabs for Task Manager is that the glimpse you get of system performance is only for a short length of time. For an immediate problem, this is a great tool for troubleshooting. For longer-range and sporadic problems that take time series data to solve, the Performance Monitor is by far the better tool to use.
The first time you use Task Manager, the Applications tab is selected, and it shows the applications that are running. The benefit of this first view in Task Manager is that if you have an application behaving sporadically, you can quickly see whether it is indeed running or not. The quick view capability of Task Manager gives you the chance to troubleshoot the immediate issues that can be impeding the performance of a Windows XP-based system.
Exploring the Performance Tab
In the Task Manager, the closest tool that approaches the functionality of Performance Monitorthe Performance tabprovides four graphical indicators of relative system performance for the point in time you are viewing them: CPU Usage, CPU Usage History, PF History, and Page File Usage History. Figure 2 shows the Performance tab in Task Manager. Notice the feedback provided in both graphical and textual format, with the key variables across the bottom of the screen.
Figure 2 The Performance tab of the Task Manager provides a quick glimpse of system performance.
Each of the measures is relatively self-explanatory, with CPU Usage showing the amount of current processor usage, expressed as a percentage of total capacity. The CPU Usage History shows the percentage of CPU capacity used over time. The PF History image shows the amount of virtual memory that has been "committed" or used, and the Page File Usage History charts virtual memory usage over time.
In the textual area of the dialog box, the Commit Charge (K) area is one of the most valuable because it defines the maximum committed virtual memory on the workstation or server. This metric provides a glimpse at current, maximum allowable, and maximum committed virtual memory.
The Physical Memory series of metrics, as reported on the Performance page of the Windows Task Manager, is also useful for determining whether the total available memory on your workstation is being used by applications currently running. This is very similar to checking the total available capacity of a hard disk after installing applicationsit's a measure of "head room" for future expansion and use of applications.