Re: more on scheduler benchmarks

Daniel Phillips (phillips@innominate.de)
Wed, 24 Jan 2001 13:29:14 +0100


Joe deBlaquiere wrote:
>
> Maybe I've been off in the hardware lab for too long, but how about
>
> 1. using ioperm to give access to the parallel port.
> 2. have your program write a byte (thread id % 256 ?) constantly to the
> port during it's other activity
> 3. capture the results from another computer with an ecp port
>
> This way you don't run the risk of altering the scheduler behavior with
> your logging procedure.

It's a technique I've used in debugging realtime systems. It works
great, but bear in mind that the out to the parallel port costs an awful
lot of cycles. You *will* alter the behaviour of the scheduler.

--
Daniel
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