nulltime

Section: User Commands (1)
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Name

nulltime - Measure CPU utilization by time available to null process

Syntax

nulltime [loops [repeats]]

Description

       Measures the time for a low priority process to execute a
        certain number of operations.
        This is used in a pair of runs, one with an unloaded system, and
        one with a loaded system.

Utilization = (1 - unloaded/loaded) x 100 %

Arguments

loops - the number of operations to be executed in a loop. (Default 10000000)

repeats - an additional multiplier of loops, in case the CPU is too fast.

Example

$ time nulltime 1000000 1000&
$ spin 10000
$ 40.607864 secs for 1000 x 1000000 operations

real       40.6
user       30.5
sys         0.0
$ time nulltime 1000000 1000
30.539456 secs for 1000 x 1000000 operations

real       30.5
user       30.5
sys         0.0

Using the above formula, during the interval measured by nulltime, the CPU utilization is 25%.

Environment

PATH=$PATH:/home/joppa/fastpac/bin/{HPPA,RISC}

MANPATH=$MANPATH:/home/joppa/fastpac/release_2/doc/60.Manuals

Known Bugs

The code is perfect.

Author

David Horton - CiTR

Copyright

Centre for Information Technology Research, 1993

This document was created by man2html, using the manual pages.
Time: 23:34:46 GMT, September 27, 2019