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Chapter 2. Resource Monitoring

Warning

Although top looks like a simple display only program, this is not the case. top uses single character

commands to perform various operations; if you are logged in as root, it is possible to change the

priority and even kill any process on your system. Therefore, until you have reviewed top's help

screen (type [?] to display it), it is safest to only type [q] (which exits top).

2.5.2.1. The GNOME System Monitor   A Graphical

top

If you are more comfortable with graphical user interfaces, the GNOME System Monitor may be

more to your liking. Like

top

, the GNOME System Monitor displays information related to overall

system status, process counts, memory and swap utilization, and process level statistics.

However, the GNOME System Monitor goes a step further by also including graphical representa 

tions of CPU, memory, and swap utilization, along with a tabular disk space utilization listing. Here

is an example of the GNOME System Monitor's Process Listing display:

Figure 2 1. The GNOME System Monitor Process Listing Display

Additional information can be displayed for a specific process by first clicking on the desired process

and then clicking on the More Info button.

To view the CPU, memory, and disk usage statistics, click on the System Monitor tab.

2.5.3.

vmstat

For a more concise view of system performance, try

vmstat

. Using this resource monitor, it is pos 

sible to get an overview of process, memory, swap, I/O, system, and CPU activity in one line of

numbers: