Hi! On 02:01 Sat 28 Aug , Pablo Antonio wrote: ... > I want to know if it's possible to create a real-time process with > SCHED_FIFO policy that starts running and never lets any other process > run again. Yes, it should be. However hardware interrupts will still arrive. > I had read that processes in SCHED_FIFO usually run until a) they block > themselves by calling some syscall (for example, an I/O request), b) > they are preempted by some higher priority process or c) they decide to > yield the processor. So I thought that technically it would be possible > to create a process that "takes over" the processor from all the other > processes: Just create a SCHED_FIFO process that loops infinitely. > > However, when I tried this it didn't work. Someone told me about > sched_rt_runtime_us and sched_rt_period_us, which acted like a > protection for this cases. So I tried both setting sched_rt_runtime_us > to -1 and setting both values to the same number, but it didn't work > either: I can switch to another terminal, execute top and see the > process running. This is weird. Are you sure that you have put the process in the SCHED_FIFO queue and assigned a static priority > 0 via sched_setscheduler? If you start top and look in the PR column you should see "RT". > What am I doing wrong? Is there some option in the kernel I have to > enable/disable? I do not think that there is an option about this. -Michi -- programing a layer 3+4 network protocol for mesh networks see http://michaelblizek.twilightparadox.com -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
