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QPS(1) General Commands Manual QPS(1)


qps - Visual Process Manager


qps [ options ]


qps is a monitor that displays the status of the processes currently in existence, much like top(1) or ps(1). The user interface uses the Qt toolkit, and most operations should be fairly intuitive.

The process list is sorted by the highlighted field. Click on another title to change; click again to reverse the sorting order. Rearrange the columns by dragging the titles.

Left-clicking on a process selects or deselects it. Shift-click to select multiple processes. The PIDs of selected processes can be pasted into other applications (this option can be disabled).

The right mouse button pops up a context menu, which duplicates some functions from the main menu for convenience. It works both on processes and on the column headings.

Control-clicking in the process table selects all processes with the same displayed value in the particular column clicked in. For instance, to select all processes owned by "joshua", keep Control pressed while clicking on "joshua". Shift and Control together produces the expected result.

In Tree mode, the parent-child relations between processes is shown in a more obvious way. Click on the triangles to show or hide an entire subtree. Sorting only affects siblings; the tree structure imposes the global order.

To change the time-sharing priority of the selected processes, type the new priority in the Renice... dialog. The new nice value should be in the range -20 to 20; 0 is the default. A larger number means that the process gets less CPU time. Only the super-user may decrease the nice value.

The Change Scheduling... dialog allows the super-user to change the scheduling policy of the selected processes (using Posix.1b scheduling control). Normal processes are set to SCHED_OTHER and have static priority 0; (soft) real-time processes have the policy SCHED_FIFO or SCHED_RR and a static priority in the range of 1 to 99. (See sched_setscheduler(2).) Solaris has additional scheduling policies, but right now qps doesn't allow setting these.

By default, the process display updates every 5 seconds. To change, type the new update period in the Update Period... dialog. The units min, s and ms may be used (if none, seconds are assumed). You can force an update by pressing the space bar or clicking the Update button. qps will consume a lot of CPU time if the update period is short or zero. If iconified, however, qps will use very little CPU.

The USER field shows the real user ID. If the effective user ID of a process is different from its real user ID, a plus sign (+) is appended to the user name; if it is the super-user, an asterisk (*) is appended.

The load, CPU, memory and swap displays in the status bar can be toggled between graphic and text representations by clicking on them, or by settings in the Preferences... dialog. The load numbers shown are the number of jobs in the run queue averaged over 1, 5 and 15 minutes.

The swap bar will turn red if free swap space falls below a certain value, which can be changed in the Preferences... dialog. The number can be entered in K, M (megabytes) or % (percent of total swap space). The default is 10%.

On SMP (multi-CPU) machines running Solaris 2.6 or Linux 2.1.x or later, the CPU stats will be shown for each processor in vertical mode, and the average of all CPUs in horizontal mode.

For displaying the WCHAN field as symbols, the kernel symbol file is needed. qps will search for it in the following locations:


where RELEASE is the kernel release number, for instance "2.0.29". If the file isn't found or unreadable, hexadecimal addresses will be displayed instead. The prefixes "sys_" and "do_" are stripped from the symbols before they are displayed. Under Solaris, symbolic names are currently not supported and hexadecimal addresses will always be shown.

The View Details menu item opens a window that shows different aspects of the selected processes. Double-clicking on a process has the same effect. All information is only available to the owner of the process (and to the super-user).

The Sockets table (Linux only) shows the currently used TCP and UDP sockets. If Host Name Lookup is checked in the Preferences dialog, a host name lookup will be done for each IP address. This is done by a background process but can take a while for difficult cases (but once looked up, addresses are cached).

The Memory Maps table shows the process's memory mappings. In Linux 2.0.x and Solaris, the file names are not given. Anonymous mappings (allocated memory not bound to a file or device) are marked (anonymous).

The Files table shows the process's open files. In Linux 2.0.x, the files are given on the form [AABB]:inode, where AA and BB are the device major/minor numbers in hexadecimal.

The Environment table shows the process's environment variables. Note that this is the environment with which the process was started, not necessarily incorporating later changes. Some processes that modify their command line, notably sendmail(8) and ftpd(8), may use the environment space for this, showing nonsense in this table. Clicking on the field headings changes sorting order as usual. (On Solaris, only the first 8K of the environment are shown. It will be fixed if it turns out to be a limitation.)

Find Parent and Find Children will select the parent/children of the selected processes, and center the table on the first of them. Find Descendants will select the tree of all children of the selected processes.

If Include Child Times is selected in the Options menu, the TIME field will show the sum of the CPU times used by the process and all of its children.

You can specify commands to be run on the selected processes by bringing up the Edit Commands... dialog. The "Description" of each command is what appears in the menu; the "Command Line" is a shell command (executed with /bin/sh). Before the command is passed to the shell, the following substitutions are made:

with the PID (Process ID) of the selected process
with the short command name of the process
with the complete command line of the process
with the name of the (real) owner of the process
with a literal '%'.

Any other % + letter combination is removed. The command line will be run once for each selected process (in unspecified order).


(valid in most contexts)

Close the active window (except the main window)
Quit qps.
Force an update of the displayed tables.
Iconify qps.


-display display
sets the X display (default is $DISPLAY)
-geometry geometry
sets the geometry of the main window of qps
-background color
sets the default background color and an application palette (light and dark shades are calculated). This doesn't work very well at the moment.
-foreground color
sets the default foreground color. This has limited use as well.
-title title
sets the application title (caption).
-style style
sets the application GUI style. Possible styles are motif and windows. (If you are using Qt 2.x, the styles cde and platinum are also available.)
-font font
sets the application font
starts the application iconified.
prints the version of qps and the Qt library, and exits.
prints a summary of command-line options and exits.


QPS_COLORS contains color specifications of comma-separated name:value pairs, where name is one of the following:

cpu-user, cpu-nice (Linux), cpu-sys, cpu-wait (Solaris), cpu-idle, mem-used, mem-buff, mem-cache, mem-free, swap-used, swap-free, swap-warn, load-bg, load-fg, load-lines, selection-bg, selection-fg

value is an X11 color name, either a symbolic name like "salmon" or an RGB color like #c5b769.


/proc kernel information pseudo-filesystem
$HOME/.qps-settings saved settings between invocations
/etc/services port number to service name mapping (Linux) kernel symbol map for WCHAN (Linux)


ps(1), top(1), kill(1), free(1), renice(8), proc(5), sched_setscheduler(2)


Mattias Engdegard (


qps is free software and may be redistributed under certain conditions. See the GNU General Public License for details.


qps is too big and too slow.

The %CPU number isn't accurate at very short update intervals due to timer granularity.

The %WCPU field isn't recalculated when qps is iconified, so it might take a while to readjust when the window is deiconified again.

The WCHAN field doesn't show a function name if a process sleeps in a location outside those in (for instance, in a kernel module), but a hex address instead. The function name can then be found in /proc/ksyms but has to be found by hand right now.

The CPU indicator in the status bar will display nonsense in SMP systems running Linux 2.0.x due to a kernel bug.

Adding/removing CPUs at runtime will probably confuse qps.

Sept 30 1999 4th Berkeley Distribution