Messages in this thread | | | Date | Sat, 30 Oct 2004 22:15:48 +0200 | From | Florian Schmidt <> | Subject | Re: [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4] |
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On Sat, 30 Oct 2004 15:52:04 -0400 Lee Revell <rlrevell@joe-job.com> wrote:
> Yup there is definitely something not right:
[snip]
> You should modify the program to print something when it sees a big > miss. This would make it easier to figure out what kind of system > activity triggers the problem.
right, i just wanted to avoid doing that from the process that polls itself, because a std::cout << "ugh!" << std::endl; might already be enough to skew the following irq's, right?
anyways, this new version [just upped] prints a line when a missed irq was detected. Also this version understands a third parameter which acts as an upper threshold. A line is printed when the difference of the cycle count of two consecutive wakeups is greater than the threshold.
run it once w/o threshold on an idle system to see what a useful thresh would be.
i use it like this for example:
./rt_wakeup 1024 50000 1200000
What's the best way to find out the cycles/s of the cpu? This way the input/output could become a little nicer [because then i can calculate programatically how long a "perfect" period should be in cycles].
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