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    SubjectRe: CPU Loading
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    Date
    On Thu, 2006-10-26 at 22:37 -0700, Indian Mogul wrote:

    > How can I load the CPU such that the scheduling time
    > slice is insuffucent for mplayer to playout the video?
    > To the mplayer the system thus appears "slow" ?

    :) unusual request.

    The proglet below, which someone posted a while back, should meet your
    needs nicely. Fire up a few copies in the background with args like
    5000 6000 7000 8000 9000.., and mplayer should become decidedly unhappy.

    The scheduler round robin schedules tasks which it has classified as
    interactive (tasks which sleep somewhat regularly basically) at a higher
    rate than their timeslice to reduce latency, but the more tasks
    circulating at the same priority (or above) as mplayer, the bigger the
    latency hit mplayer will take.

    -Mike

    #include <stdlib.h>
    #include <unistd.h>

    static void burn_cpu(unsigned int x)
    {
    static char buf[1024];
    int i;

    for (i=0; i < x; ++i)
    buf[i%sizeof(buf)] = (x-i)*3;
    }

    int main(int argc, char **argv)
    {
    unsigned long burn;
    if (argc != 2)
    return 1;
    burn = (unsigned long)atoi(argv[1]);
    while(1) {
    burn_cpu(burn*1000);
    usleep(1);
    }
    return 0;
    }


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