[TriLUG] bogo-bogomips & Scratch tutorial on RPi Re: Raspberry Pi followup

[Pete Soper]

(Cross-posting, as many Splat Spacers are not on the TriLUG list).

A few more numbers.

Clock setting        Reported bogomips     C program triple-for-loop 
elapsed seconds

   700                      697                              16.5
   800                      697                              14.5
   900                      697                              12.9

The C code times were repeatable after the pages had been loaded with 
the first execution.

Note that there are a few magic parameters put into the config.txt file 
when raspi-config is used to configure over-clocking: it isn't just one 
parameter except with the mildest (800mhz) setting, so don't think you 
can just edit the file and jam big numbers into the one parameter when 
going higher than default. Use raspi-config so you can be reminded of 
the fact that you ought to just buy another RPi rather than burn out the 
first one. :-)

The same first grader who said "I've used that before" Thursday night 
came and gave a Scratch tutorial.

-Pete


On 01/14/2013 12:21 PM, Bill Farrow wrote:
> On Mon, Jan 14, 2013 at 11:47 AM, Alan Porter <porter at trilug.org> wrote:
>> What new stuff did folks learn?
> I discovered that the reported bogomips value from /proc/cpuinfo was
> not an accurate reflection of the CPU speed on the RasPi.  I left the
> workshop scratching my head, not entirely sure why we got these
> results, but it was fun trying.  We under-clocked and over-clocked a
> board and got these results, and Pete wrote a small C program to
> verify the CPU performance changes.
>
> MHz    bogomips
> 200      199
> 700      697
> 800      697
>
>> What awesome project ideas were born?
> There were two motorola mobile phone docking laptops with a RasPi
> plugged into the them instead.
>
> Bill