Re: bogomips ???

Richard B. Johnson (root@chaos.analogic.com)
Fri, 23 Apr 1999 08:49:29 -0400 (EDT)


On Fri, 23 Apr 1999 kernel@vdr.qc.ca wrote:

> Hello everyone,
>
> I have a simple question. What the h... is a bogomips ? I think it
> has to do with the time a cpu takes to do a certain number of software
> loops. Is that it ? If so, how is the number measured ?
>
>
> Papi

There are some timeouts in the kernel that need to be less than any
available hardware timer ticks. So, upon startup the kernel measures
the time necessary to perform a simple loop. This calibrates the loop
so it can be used for very short timing. The result of the calibration
is saved and displayed as 'BogoMips'. The larger the value, the faster
your CPU can perform this simple timing loop. Therefore, it provides a
relative indication of CPU speed.

Cheers,
Dick Johnson
***** FILE SYSTEM WAS MODIFIED *****
Penguin : Linux version 2.2.6 on an i686 machine (400.59 BogoMips).
Warning : It's hard to remain at the trailing edge of technology.

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