On 13/5/23 09:00, onefang wrote:
>
> Linux has a RT kernel, I use it on my Devuan desktop for music
> production. Did I bring this back on topic? B-)
>
>
The linux kernel is pretty snappy but it's not possible get 'true'
deterministic performance for a user space applcation.

I use linux all the time for 'real time' applications such as audio
streaming and processing. If you use a soft SIP phone so are you.

The problem comes down to microsecond timed control of hardware such as
setting an output bit at a precise time. Linux does not guarantee that
so you have to rely on hardware or run some clunky real time OS such as
RTOS.

Luckily the vast majority of applications don't need that precision. I
gave the example of ArduPilot that is a highly complex system
interfacing to many sensors and data sources and sinks and relying in
precise timing. It did not use RTOS (I think some later versions may).
It just required intelligent coding and the use of hardware for the
precision operations.

If you stick with linux you have pthreads for any conceivably complex
application architecture - though any application that needs more than
two threads per core is almost certainly badly designed.

I also think RTOS and equivalents are highly obsolete these days and
seem mainly used by legacy developers keen to keep themselves in a niche
job.

--

Jeremy