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Top (Unix)
Encyclopedia
top is a program found in many Unix-like
operating systems. It produces an ordered list of running processes selected by user-specified criteria, and updates it periodically. Default ordering by CPU
usage, and only the top CPU consumers shown (hence the name.) top 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.
top is useful for system administrator
s, as it shows which users and processes are consuming the most system resources at any given time.
On Solaris, the roughly equivalent program is prstat.
The ps
program is similar to top, but instead produces a snapshot of processes taken at the time of invocation.
Unix-like
A Unix-like operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification....
operating systems. It produces an ordered list of running processes selected by user-specified criteria, and updates it periodically. Default ordering by CPU
Central processing unit
The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...
usage, and only the top CPU consumers shown (hence the name.) top 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.
top is useful for system administrator
System administrator
A system administrator, IT systems administrator, systems administrator, or sysadmin is a person employed to maintain and operate a computer system and/or network...
s, as it shows which users and processes are consuming the most system resources at any given time.
On Solaris, the roughly equivalent program is prstat.
The ps
Ps (Unix)
In most Unix-like operating systems, the ps program displays the currently-running processes. A related Unix utility named top provides a real-time view of the running processes....
program is similar to top, but instead produces a snapshot of processes taken at the time of invocation.
See also
- HtopHtop (Unix)Htop is an interactive system-monitor process-viewer written for Linux. It is designed to replace the Unix program top. It shows a frequently updated list of the processes running on a computer, normally ordered by the amount of CPU usage. Unlike 'top', Htop provides a full list of processes...
- nmonNmonnmon is a popular system monitor tool for the AIX and Linux operating systems.- Description :The original nmon was a freely downloadable tool for AIX 4.3 from the AIX wiki. It was also rewritten for the Linux operating system running on IA-32, x86-64, RS/6000 and Power processor and Mainframe and...
— a system monitor tool for the AIX and Linux operating systems.
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 HtopHtop (Unix)Htop is an interactive system-monitor process-viewer written for Linux. It is designed to replace the Unix program top. It shows a frequently updated list of the processes running on a computer, normally ordered by the amount of CPU usage. Unlike 'top', Htop provides a full list of processes...