The Process Table gives you a list of processes on your system. The list can be sorted by each column. Just press the left mouse button at the head of the column.
Use the What's This help for the columns titles to get additional information about the value displayed here.
In the context menu of a process in the list view you find additional actions like changing the priority, sending signals to the process, switching to the application window, showing detailed memory information and killing the process.
The list shows the following information about each process. Please note that not all properties are available on every operating system.
Table 2.1. Default Columns in the Process Table
|Name||The name of the executable that started the process|
|Username||The user who owns this process|
|CPU %||The current total CPU usage of the process, divided by the number of processor cores in the machine|
This is the amount of real physical memory that this process is using by itself, and approximates the Private memory usage of the process.
It does not include any swapped out memory, nor the code size of its shared libraries.
This is often the most useful figure to judge the memory use of a program.
|Shared Mem||This is approximately the amount of real physical memory that this process's shared libraries are using. This memory is shared among all processes that use this library|
|Window Title||The title of any window that this process is showing|
Table 2.2. Additional Columns in the Process Table
|PID||The unique Process ID that identifies this process|
|TTY||The controlling terminal on which this process is running|
|Niceness||The priority with which this process is being run. For the normal scheduler, this ranges from 19 (very nice, least priority) to -19 (top priority)|
|CPU Time||The total user and system time that this process has been running for, displayed as minutes:seconds|
|IO Read||The number of bytes read. The Display Units and the Displayed Information can be changed using the context menu of this column header|
|IO Write||The number of bytes written. The Display Units and the Displayed Information can be changed using the context menu of this column header|
|Virtual Size||This is the amount of virtual memory space that the process is using, included shared libraries, graphics memory, files on disk, and so on. This number is almost meaningless. Use the context menu to select the Display Units|
|Command||The command with which this process was launched|
At the top of the table you find three controls which will be described now from left to right.
If you have selected one or more processes you can press the button to kill them. A so called SIGKILL is sent to the processes which causes them to terminate immediately. If these applications still have unsaved data this data will be lost. So use this button with care.
Filter which processes are shown by the text given here. The text can be a partial string match of the Name, Command or Window Title of the process. It can also be a Username or a Process ID number.
The Process Filter can be used to reduce the number of processes displayed in the table. You can filter out processes you are not interested in. Currently you can display All Processes in a flat or tree view, System Processes only, User Processes only, your Own Processes only or Programs Only.
The tree view has been designed to show the relationships between the running processes. A process that is started by another process is called the child of that process. A tree is an elegant way to show this parent-child relationship. The init process is the ancestor of all processes.
If you are not interested in the children of a particular process you can click on the little box to the left of the parent and the subtree will collapse. Another click on that box will unfold the subtree again.