I am currently looking at a compact PCI  (cpci) processor board from General
Micro Systems called the C2P3.  (www.gms4vme.com)

According to their article (ramp_article.pdf on their website), they acheive a
90 to 100 percent speed improvement with the second processor (over a typical 30
- 40 percent speed improvement normally recieved by a second cpu) by pushing all
the "real-time" demands on to the second processor.

Two questions:

1 - Could rtlinux be modified to run soley on the second cpu?  This would let
the primary cpu run normal linux, and the second run all time critial apps?

2 - If you had all real-time code running on one cpu alone, what is the 
achievable max periodic rate?  I am suggesting here you would not context 
switch in / out of real-time but instead read the real-time clock in pentium
processors to determine when to switch from task to task (have a stall proceess
that waits for next schedule point).  The purpose of the stall loop remove the
need to "interrupt" the processor with a hardware timer, and thus loose time
servicing the interrupt.

My final goal is to have a realtime application (single task most likely) that
performs an action every 0.01ms (100khz).  With a pentium 90 running in dos I
was only able to achieve 5kh due to interrupt handling overhead.  I have heard
talk about the pentium real-time counter being used to measure time to
micro-seconds.  Thus I assume if the task were short enough, one could perform
that task then wait for the next schedule point to perform that task again.

Does this make sense?

 Thanks,
  Kirk Smith
  Software Engineer
  Micro Systems Engineering
  [EMAIL PROTECTED]



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