Chapter 3.1.2 htop ================== htop is an ncurses text interface task manager that can be controlled by the keyboard. htop also closes unresponsive programs by killing the process. Usage ------ To view how much RAM is being used on your system is under :guilabel:`Mem` and then a [ number based on how many Gigabytes of memory. The :guilabel:`Swp` line lists how much swap is used. The numbers going down with a bar with a percentage next to them display CPU usage on each of your CPU cores. To see how many process are running on your system see the :guilabel:`Tasks` row. :guilabel:`Load average` shows your system load over the past one five and fifteen minute is why there are three numbers see `Wikipedia load (computing) `_ for more information. :guilabel:`Uptime` shows how long your computer has been booted. After the bottom there is a green bar that says :guilabel:`PID` for the Process ID of a user, The user the process responds to, :guilabel:`RES` is how much RAM the process is currently using. :guilabel:`CPU%` shows how much as a percent of CPU time the process is using, :guilabel:`MEM%` is a percent of the RAM your process is using. :guilabel:`Time` shows how long the process has been running. :guilabel:`Command` shows the command line command of the process. To view any cut off part of the :guilabel:`Command` field press the :kbd:`Right Arrow` to view the cut off area of the window. To move your window back to where it was press the :kbd:`Left Arrow` key. To select the process below the currently selected one press :kbd:`Down Arrow` to select the process below. To select the process above the currently selected one press :kbd:`Up Arrow` to select the process above. To select the next group of processes on your screen press :kbd:`Page Down` or move the scrollwheel on the mouse down. To select the previous group of process on your screen press :kbd:`Page up` or move the mousewheel up. To choose the last process on your system press the :kbd:`End` key. To choose the first process press the :kbd:`Home` key. .. image:: htop.png You can press :kbd:`F1` or :kbd:`?` to bring up a help dialog on htop. Pressing :kbd:`F3` or :kbd:`/` lets you search for a particular process. Pressing :kbd:`F4` makes it so you can only see processes matching a certain pattern. To get out of the view of your search for a pattern press the :kbd:`Escape` key. To reverse sort order press :kbd:`Shift +I`. Pressing :kbd:`F5` is what you press to view the processes in a tree. To get back to the default view press :kbd:`F5` again. Pressing :kbd:`F9` lets you kill a process with different signals to send to the process and 15 will terminate the process while 9 will Kill it. Lastly pressing :kbd:`F10` or :kbd:`q` will quit htop and return you to a terminal. .. image:: htop-filter.png To change how your process are sorted press :kbd:`F6` which will bring up your own menu to sort by by :guilabel:`PID`, :guilabel:`USER`, :guilabel:`Priority`, :guilabel:`NICE`, :guilabel:`M_Size`, :guilabel:`M_Resident`, :guilabel:`M_Share`, :guilabel:`State`, :guilabel:`Percent_CPU`, :guilabel:`Percent_Mem`, :guilabel:`Time`, or :guilabel:`Command`. To select a menu item press :kbd:`Enter`. :kbd:`F2` brings about a customizable settings on htop. The :guilabel:`Meters` options brings up meters like CPU average. To move a meter press :kbd:`Enter` and press the arrow keys to move in the direction of the meter you want to select. To see what kind of meter you have it will be shown in brackets. The :guilabel:`Display Options` has option for different ways to display in htop. To toggle an option on press :kbd:`Spacebar`. The :guilabel:`Colors` tab brings up different color schemes for htop. To select a different color scheme press the :kbd:`Up arrow` or :kbd:`Down arrow` keys. To select a new color scheme press the :kbd:`Spacebar` key. To move the meter press :kbd:`Enter` and then press the arrow keys to move where it goes. .. image:: htop-setup.png To change what columns end up showing select :guilabel:`Columns` on the setup menu. The column :guilabel:`Active Columns` shows what columns you will have on htop with the top being the leftmost column in htop and the bottom being the rightmost. To select a different column press :kbd:`Up arrow` or :kbd:`Down arrow`. To move a column up in the list press :kbd:`F7`. To move a column down press :kbd:`F8`. To remove a column press :kbd:`F9`. To see what other columns there is the column :guilabel:`Available Columns`. To add a column when having :guilabel:`Available Columns` and select the column you want and press :kbd:`F5`. Version ------- Lubuntu ships with version 3.0.3 of htop. How to launch ------------- To launch htop from the menu :menuselection:`System Tools --> Htop` with the Icon that looks like the green H made out of text or run .. code:: htop from the command line.