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On Tue, 23 Jun 2026 12:15:08 +0200 Juri Lelli wrote: [...] > - At 1ms task periods, the dl-server period is the critical tuning > parameter, less the bandwidth. A 10ms dl-server with 60% bandwidth > caused ~10% miss rates because the worst-case throttle gap (4ms) > spanned multiple 1ms deadlines. Switching to a 2ms dl-server period > at just 30% bandwidth eliminated all misses. > > - A simple Rule of thumb might be to set the dl-server period to at > most 2x the shortest task period in the cgroup (e.g., 2ms dl-server > for 1ms tasks, 10ms for 10ms tasks). Would you (and Luca?) agree or > would you suggest something different? With one single RT task in the cgroup (or with multiple synchronized RT tasks having the same period), I agree... Technically, the cgroup period P should be such that P - Q = T - WCET (where "Q" is the cgroup's runtime and "T" is the period of the task), but to see missed deadlines you need a relevant competing deadline (or HCBS) workload. So, yes, I agree with your findings above. If we consider multi-core analysis, or multiple RT threads with different, non synchronized, periods, then analysis tool by Yuri (leveraging CSF analysis from real-time literature) is needed... But that is pretty pessimistic. The rule you suggest above is a better starting point in practical situations. Luca