Hi Jackson, Nicolas, On 20/06/24 19:33, Nicolas Dufresne wrote: > Hi Jackson, Devarsh, > > Le mercredi 19 juin 2024 à 23:56 +0000, jackson.lee a écrit : >> Hi Devarsh >> >> If there is no feeding bitstreams during encoding and decoding frames, then driver's status is switched to suspended automatically by autosuspend. >> And if we don’t use autosuspend, it is very difficult for us to catch if there is feeding or not while working a pipeline. >> So it is very efficient for managing power status. >> >> If the delay is very great value, we can adjust it. > > One way to resolve this, would be if someone share measurement of the suspend / > resume cycle duration. With firmware (third party OS) like this, the cost and > duration is few order of magnitude higher then with more basic ASIC like Hantro > and other single function HW. > > Yet, 5s might be to much (but clearly safe), but getting two low may means that > we suspect "between two frames", and if that happens, we may endup with various > range of side effect, like reduce throughput due to suspend collisions, or even > worse power footprint. Some lab testing to adjust the value will be needed, we > have very little of that happening at the moment as I understood. > Okay I see the intention here is that if there is a process holding the vpu device handle and the input feed is stalled for some seconds due to network delay or CPU throughput then after a specified timeout say 5 seconds we want to suspend even if the process is still active and holding the vpu device handle ? I agree then if we want to support this feature a safer/slightly larger value is required to avoid frequent suspend/resume due to network jitter or any other bottleneck and maybe 5s is a good value to start with. But if last instance is closed/stops streaming and there is no process holding the device handle anymore then I think we should suspend immediately without any delay. Regards Devarsh
