"Testing results in screenshot are interesting. Haven't looked at them very closely, but that's what I noticed- uptime 17.0 is not 17%. Still not clear on CPU utilization vs load, are we.- On the terminal in upper right corner load steadily grows as…"
"That's what I expected, actually. "stress -c 1" means that the system was not highly loaded, load barely above 1.0. And you just loaded CPU, without stressing memory subsystem. Cursory and inadequate testing, it seems to me.
"Roberto: Yes, PRU is important for using BB as a flight controller. I read somewhere that the next release of BeagleBone will not use Texas Instruments CPU, however, so I don't know what will they do about interfacing to external sensors then.
"Victor, you did not specify the options of "stress" command that you used in your testing, even though in previous discussion I asked about it, I think, more than once. You also did not provide any information about system load during the testing,…"
"I am talking about the operating system that is used to run the flight control software. Aircraft may fly without using a real-time software, but it runs the risk of freezing up and crashing, if the system used to run flight control software gets…"
"@Dinuka: "This means that you have about 5-10ms from the time the sensors are read till you need to produce actuator signals. I'm quite confident that a beagle bone can handle that with right thread priorities."
"PRU-ICSS subsystem in TI ARM processor used by BeagleBone is really a separate dedicated microcontroller on the same chip. Other platforms such as Odroid or RPi do not have similar feature, and port PRU-ICSS part to them is plain impossible.
"If by "Linux" you mean mainline kernel without RT hypervisor or PREEMPT_RT patch, than there is no way to tune it to guarantee maximum latency. Your statement to the contrary is just plain wrong, and you testing does not establish it.
"Dinuka - it is not possible to have control code real-time on Linux computer, because Linux is not real-time operating system. There're real time patches, but they are in effect another real-time operating system, that runs Linux as a process.