Hi Florian, On 2024-12-20, Florian Paul Schmidt <mista.tapas@xxxxxxx> wrote: > I'm playing around with a Raspberry Pi 5 and a PREEMPT_RT kernel (raspberry > pi 6.13.y branch) and wonder about the latencies I see. First I tried > cyclictest and saw latencies in the upper 50s up to 80s or so under a > kernel compile load. ... > I still wonder though: How come the latencies are so large? Is the > raspberry pi platform just not suited to reach lower latencies? Is > everything working as expected? Are maybe the raspberry pi > patches responsible for latency sources which are invisible in the > traces? I there any hope for getting these latencies a little more > under control? There are various kernel configurations that affect latency. But I am curious... Why do you think a maximum latency of 80us on an $80 board is large? What maximum latencies are you expecting? And why do you think it is not "under control"? John Ogness
