The Preferences Dialogue

Figure 1-7. The preferences dialogue of gtop

The gtop program is extremely configurable. As a result, the Preferences dialogue box is rather large. It is split into seven main areas:

Only five of these show up in the selection area at the top of the box. There is a pair of arrows to the right of these five. Clicking those arrows alters the selected area. To reach the two sections not initially displayed, use these arrows to cycle through the options. To select a preference section, click on the name of the section.

Global preferences

The session management checkbox will save the state of gtop's session if checked. This includes not only the preferences but the window position. Next time you run it, it will remember and use those.

Despite being in the global preferences section, the update times for the graphical summary refer to the moving graphs in the processes display.

The textual summary refers to the statusbar found at the base of the gtop display.

MDI mode refers to the multiple document interface, which is how GNOME displays more than one document in an application. This guide has been written under the assumption that you are using the default of 'notebook'. More details on this are available in the GNOME Users Guide in the control-center section.

Processes

Preferences in this section affect the process window.

The font selector will invoke a new dialogue window which allows you to examine and choose different fonts which should be used for the processes window.

The details section will alter how the details of a process you select with the mouse button (either double-clicking on the process with button one, or selecting it with button one and choosing the 'details' entry on the menu found by pressing button two) are displayed to you.

Cumulative timings in the miscellaneous section refers to toggling whether the Time field in the process display shows the time used by that process only (the default, with this unchecked) or the time used by that process plus all the processes it spawned (shown if you enable this) and which are now dead.

Process Fields

This allows you to select which fields should be displayed on the process display and how many characters wide they should be. There are three fields which are not displayed by default: 'resident', 'utime', and 'stime'. They can be selected here. And any field can be unselected and removed from the process display.

Summary

The font selector will invoke a new dialogue window which allows you to examine and choose different fonts which should be used for the statusbar: the single line of information at the base of each display.

The graphical summary refers to the graphical summary on the processes window. The textual summary refers to the statusbar at the base of all windows. Unchecking the text summary box removes that line completely. Checking the text summary box but not the status bar results in the hostname section being removed from the display.

Note that checking the memory and swap statistics checkboxes for the textual summary (unchecked by default) will redraw the window to be very much wider to fit the extra information in. Although the window can be resized, if you have a screen size of 640x480 or 800x600, you may find this too wide for comfort initially.

Summary colors

This section deals with the colours used on the processes window in the small graphs at the top. Clicking on any colour will bring up the GNOME colour wheel for you to alter the colours displayed.

Memory Usage

This section allows you to refine the display on the memory use window. The minimum sizes are the minimum size required for a process to be displayed as a separate entity. The remainder are grouped together at the bottom of the display. The process selection helps cut down (or expand) the processes whose memory use is displayed. User processes means only those processes owned by the user who started gtop. Controlling tty means only those processes which run in a terminal are displayed, removing many background system daemons from the display.

Filesystem usage

This section allows you to refine the display on the filesystem usage window. You can restrict your view to only certain types of filesystems. Most of these are designed for particular operating systems. However, it is often the case that other operating systems know how to read them too.

You can also alter what gtop looks for when counting up what is free, used or the total. These are radio buttons, so you can only pick one at a time. You can choose to view inodes, one-kilobyte blocks, or one-kilobyte blocks including reserved blocks. Inodes are where UNIX stores information about files: the permissions, the size, where on the filesystem it lives, everything but the name of the file, essentially. Reserved blocks are part of the filesystem which only root can write to. They take up about five to ten per cent of the filesystem. This helps stop the disk filling completely as the result of user actions. But it also means that reserved blocks are not available for users to use. The most useful view is probably the default of one-kilobyte blocks, but you can select inodes or one-kilobyte blocks including reserved blocks if you choose.

Graph

This section allows you to alter the appearance of the large graph on the left in the memory usage and filesystem usage windows. The geometry sizes are in pixels. The colours are altered in the same way as the colours of the process window's graphics: by clicking on a colour to invoke the GNOME colour wheel.