Re: profiler which does not just sum up used time

To conclude, on a system with only one or two CPU's (cores) a higher priority thread will run for at most ~5 second before it will get pre-empted. The time it will get off a CPU depends on the other threads activity, but keeping a single core busy for such a long period (~5 seconds) will probably accumulate that much lower priority threads to become ready, so that your thread will get pre-empted for at a complete quantum or more.

Thanks for the details. I was aware that to prevent starvation the threads would over time build up priority. I did however beleive that their priority would never go above high.
An application can be set to realtime priority and according to what I have read, this should prevent preempting entirely, but that still does not seem to be the case.. Or perhaps it has to do with me not being able to set a threads priority to realtime. Only the application can be realtime.

How would you suggest that I move on now? I have an app doing rendering and it occationally gets preempted (or so I beleive, can I test is this is indeed the cause somehow?) and when that happens I lose a few frames. I can not live with even a single lost frame unless the rendering is very complex, which it is generally not. What could be a solution to this?

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