Re: BogoMIPS ?

[cjw44@cam.ac.uk (Colin Watson)]

webmaster@euronetwork.com wrote:
>could anyone please tell me what "BogoMIPS" at bootup means?

See the BogoMips mini-HOWTO, which you should be able to find in
/usr/doc/HOWTO or /usr/share/doc/HOWTO depending on your version of
Debian.

       `MIPS is short for Millions of Instructions Per Second.  It
       is a measure for the computation speed of a program.  Like
       most such measures, it is more often abused than used prop­
       erly (it is very difficult to justly compare MIPS for dif­
       ferent kinds of computers).

       BogoMips are Linus's invention. The kernel (or was it a
       device driver?) needs a timing loop (the time is too short
       and/or needs to be too exact for a non-busy-loop method of
       waiting), which must be calibrated to the processor speed of
       the machine. Hence, the kernel measures at boot time how
       fast a certain kind of busy loop runs on a computer. "Bogo"
       comes from "bogus", i.e, something which is a fake. Hence,
       the BogoMips value gives some indication of the processor
       speed, but it is way too unscientific to be called anything
       but BogoMips.

  The reasons (there are two) it is printed during bootup is
  that a) it is slightly useful for debugging and for checking
  that the computers caches and turbo button work, and b)
  Linus loves to chuckle when he sees confused people on the
  news.'

-- 
Colin Watson                                           [cjw44@cam.ac.uk]