View the table below to see a summarization of the available commands.
Eventually, you will encounter processes that either aren't working correctly or aren't working at all. Problems with processes usually manifest themselves as degraded system performance. For example, problematic processes may consume vast quantities of memory, causing your machine to thrash
, or they may consume lots of CPU resources, slowing down your system. Linux provides several diagnostic and control commands that allow you to manage processes. With these tools, you can identify troublesome processes, stop them, and control their behavior. Linux identifies processes by ID number. A process ID (PID)
is a unique, non-negative number that you use to identify and control processes. Commands that list processes do so by showing you each process's ID, along with other information such as program name and owner. Commands that manage processes often expect you to provide the process ID of the process you want to control.
If you believe processes are causing your system to behave poorly, you'll need to identify and stop the culprits. The list below outlines the
gtop. Examine the %CPU and %MEM fields for a process that is significantly astray. Processes should take a reasonable amount of available CPU and memory, relative to other processes in the system.
- If just one process is at fault, note its PID and kill it:
kill -KILL pid. If several related processes are at fault, kill them
all by name
killall -KILL name.
- If the X Window System is responding too slowly, type Control-Alt-F2 to obtain a text login prompt. Log in as root, fix the problem as
described above, and return to X Windows by typing Control-Alt-F7.
If the problem did not stem from a runaway process, it may be troubleshooting.sbhardware related.
Click the Start Simulation button below to practice troubleshooting some processes.
An activity which requires a great deal of paging, where a process spends more time paging than executing, causing a significant negative impact on a system's performance. Thrashing occurs when there is not enough RAM to handle all the required processes,
the solution is to move a process to disk, thereby leaving enough space for other processes to complete.