RT-ers, I have a problem with the way cyclictest sets up measurement threads, but before I went and changed things I thought I would ask if people cherished this particular behavior. Currently, when cyclictest is run with multiple threads (i.e. -t option) it distributes both the sample interval and the realtime priority by adding the 'distance' parameter to the interval and decrementing the priority by one. This means if you have a distance of 500us (default), a specified RT priority of 95 and start four threads, they will be started with the following parameters: $ cyclictest -t4 -p95 Will give you: thread priority sample interval 0 95 500 1 94 1000 2 93 1500 3 92 2000 What I'd like to do is modify this logic so that when '-a' (affinity) is specified, the priority and sample interval will not be altered. I don't think there's any point in distributing the priority's and sample intervals when the measurement threads are pinned to their own CPU. So: $ cyclictest -t4 -p95 -a Would have each thread at SCHED_FIFO 95 and a sample interval of 500us. Note that this behavior also occurs when the histogram (-h) option is specified). Thoughts? Clark
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