[Coco] Kernel activity on the O-Scope

[Boisy G. Pitre]

I know posting attachments are discouraged, but in this case I hope folks don't mind.

Working on my thesis here at school gives me the opportunity to play with some nice test equipment.  While doing some other measurements, I figured I would measure the percentage of the time NitrOS-9 runs when there is no process active.  Keep in mind that every 16.67ms the clock interrupt kicks in and the code in clock.asm checks interrupts, just to the kernel so it can do its housekeeping (checks the queues, etc.), then inserts the active process into the queue, or in this case, call the CWAI instruction since there is no active process.  The shell prompt was sitting there as I captured this.

 The graph below shows the amps in yellow, the volts in green and the LIC line in purple.   The little peaks represent the clock/kernel activity... the measured time is 700us, or .7ms. 

Doing the math,  .7/16.67 * 100= 4.2%.  So 4.2% of the clock period is spent in the kernel. 


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