Be kind; don’t be snarky. You’re here to share your knowledge, not sneer down at people who bring up fairly reasonable questions.

The person put a blank statement that the Linux is unusable for the task (without giving any more information) and I responded that it is usable because we are using it for it.

As to "run of the mill software dev" this is not a snarky comment, this is just reality.

Most devs have absolutely no idea how to configure Linux at all, other than to make their application work. Not to mention configure for real time operation.

So I stand by my comment that comes from over two decades of experience in the field.

"Linux" as most people know it is unusable for this kind of task. They are correct that the standard scheduler will not really let you run anything that needs to run in real time. Your response to that is literally just "no, we did it, and you're just to dumb to understand". Imagine a third grader and and they told you that you can't take the square root of a negative number. Of course you know that imaginary numbers exist, but you'd be a jerk if you just replied to them with "you can actually but I guess some people just don't know how to do it".

Hacker News is a site that values intellectual curiosity, not snark: you should have replied with an explanation of what you are actually doing to get that kind of thing out of the Linux kernel. What value is your experience in the field to this community if you refuse to share it with others? In this case my analogy is even stronger because you could argue that explaining imaginary numbers to a third grader may be difficult, but "I set CONFIG_whatever to this value and set the kernel to never schedule my application off this core" is exactly the kind of response that would be expected in this context.

>"not sneer down at people who bring up fairly reasonable questions"

Downvoting reasonable posts that do not fit somebody's point of view without providing any constructive explanations is of course way better.

I don't care about downvotes. If somebody is here for votes then they should reassess their life's choices.

I do not care either. Real choices are made in real life. We are just talking here.

What distro or patch set did you use? According to wikipedia, the best RTLinux could do was within 15 microseconds on interrupt handlers, and within 35 microseconds of its scheduled time for processes.

It is my understanding that the other real time linux attempts ended up in similar territory, good but not sub 5 microsecond good.