time: Resource Measurement

1 
1 1 Measuring Program Resource Use
1 ********************************
1 
1 The 'time' command runs another program, then displays information about
1 the resources used by that program, collected by the system while the
1 program was running.  You can select which information is reported and
1 the format in which it is shown (⇒Setting Format), or have 'time'
1 save the information in a file instead of displaying it on the screen
1 (⇒Redirecting).
1 
1    The resources that 'time' can report on fall into the general
1 categories of time, memory, and I/O and IPC calls.  Some systems do not
1 provide much information about program resource use; 'time' reports
1 unavailable information as zero values (⇒Accuracy).
1 
1    The format of the 'time' command is:
1 
1      time [option...] COMMAND [ARG...]
1 
1    'time' runs the program COMMAND, with any given arguments ARG....
1 When COMMAND finishes, 'time' displays information about resources used
1 by COMMAND.
1 
1    Here is an example of using 'time' to measure the time and other
1 resources used by running the program 'grep':
1 
1      eg$ time grep nobody /etc/aliases
1      nobody:/dev/null
1      etc-files:nobody
1      misc-group:nobody
1      0.07user 0.50system 0:06.69elapsed 8%CPU (0avgtext+489avgdata 324maxresident)k
1      46inputs+7outputs (43major+251minor)pagefaults 0swaps
1 
1    Mail suggestions and bug reports for GNU 'time' to
1 'bug-time@gnu.org'.  Please include the version of 'time', which you can
1 get by running 'time --version', and the operating system and C compiler
1 you used.
1 

Menu

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· Setting Format      Selecting the information reported by 'time'.
· Format String       The information 'time' can report.
· Redirecting         Writing the information to a file.
· Examples            Examples of using 'time'.
· Accuracy            Limitations on the accuracy of 'time' output.
· Invoking time       Summary of the options to the 'time' command.
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