Re: Stealing ur megahurts (no, really)

["Dr. David Alan Gilbert" <linux@treblig.org>]

* John Richard Moser (nigelenki@comcast.net) wrote:

> Scrambling for an old machine is ridiculous.  Down-clocking makes sense
> because you can adjust to varied levels; but it's difficult and usually
> infeasible.  Pulling memory and mix and matching is not much better.

<...>

> This brings the idea of a cpumhz= parameter to adjust CPU clock rate.
> Obviously we can't do this directly, as convenient as this would be; but
> the idea warrants some thought, and some thought I gave it.  What I came
> up with was simple:  Adjust time slice length and place a delay between
> time slices so they're evenly spaced.

<...>

Hi John,
  While cpu downclocking helps a bit, it would be hopelessly inaccurate
for figuring out if your app would run fast enough on the given
ancient machine.  A lot else has happened to the world since the days
of the 200MHz CPU:
    * Faster memory
    * Larger caches
    * Faster PCI busses
    * Instruction set additions (various more levels of SSE etc)
    * Faster discs
    * Changes to the CPU architecture/implementation

Still, it would be interesting to see the difference in performance
of a downclocked modern processor and its 10 year old clock equivalent.

Dave

-- 
 -----Open up your eyes, open up your mind, open up your code -------   
/ Dr. David Alan Gilbert    | Running GNU/Linux on Alpha,68K| Happy  \ 
\ gro.gilbert @ treblig.org | MIPS,x86,ARM,SPARC,PPC & HPPA | In Hex /
 \ _________________________|_____ http://www.treblig.org   |_______/
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