On 2021-09-30, Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> wrote: >> With hackbench, the system is sufficiently busy to avoid the going >> into idle. > > Not just that. cyclictest's usage of /dev/cpu_dma_latency has the side > effect that it may disable some of the PM stuff in the system. > So your system appears good but then when cyclictest is gone, the > numbers go up. > > Maybe we should drop that so we observe a system without altering its > behaviour? +1 Developers wanting to explicitly cause this behavior can use --latency= to enable it. Having it on as a default is misleading. John Ogness
