Top (Unix)
From DssWiki
{{DISPLAYTITLE:{{#if:|:|}}top (Unix)}}
In most Unix-like operating systems, the top command produces a frequently-updated list of processes. The processes are ordered by amount CPU usage, with only the "top" CPU consumers shown. The top command shows how much processing power and memory are being used, as well as other information about the running processes. Some versions of top allow extensive customization of the display, such as choice of columns or sorting method.
The top command is very useful for system administrators, as it shows which users and processes are consuming the most system resources at any given time.
For a non-realtime list of processes, see ps.
[edit] History
The top command was inspired by the monitor process/topcpu command found in the VMS operating system. William LeFebvre wrote the first implementation of top in April of 1984 for BSD 4.1 while a graduate student at Rice University. It was released as an Open Source project under the BSD license, which allowed it to be included in numerous proprietary BSD and UNIX operating systems. The top command has been reimplemented many times, including several times for Linux. The usual Linux version, the most used top by virtue of Linux popularity, is a full-color windowed implementation by James C. Warner that ships with the procps package.
[edit] See also
- pstat command
- ps command
- vmstat command
- List of Unix programs
- Load (computing)
[edit] External links
- Linux top home page (procps) and man page
- BSD top home page and man page
- Alternate top programs for Linux include atop (uses process accounting) and htop (has tree view and scrolling).
{{#if: |
Unix command line programs and builtins (more) | |||
| File and file system management: | cat | chattr | cd | chmod | chown | chgrp | cksum | cmp | cp | du | df | file | fsck | fuser | ln | ls | lsof | mkdir | mount | mv | pwd | rm | rmdir | split | touch | ||
| Process management: | at | chroot | crontab | exit | kill | killall | nice | pgrep | pidof | pkill | ps | sleep | time | top | wait | watch | ||
| User Management/Environment: | env | finger | id | mesg | passwd | su | sudo | uname | uptime | w | wall | who | whoami | write | ||
| Text processing: | awk | comm | cut | ed | ex | fmt | head | iconv | join | less | more | paste | pg | sed | sort | tac | tail | tr | uniq | wc | xargs | ||
| Shell programming: | basename | echo | expr | false | printf | test | true | unset | Printing: | lp |
| Communications: inetd | netstat | ping | rlogin | traceroute | Searching: find | grep | strings | Miscellaneous: banner | bc | cal | dd | man | size | yes | |
