Work on realtime preemption for the Linux kernel got its start almost exactly 20 years ago (though it had its roots in earlier work, of course). It is fair to say that finishing that job has taken a bit longer than anybody involved would have expected. Now, though, Sebastian Andrzej Siewior has posted a brief patch series making it possible to enable realtime preemption in the mainline kernel on three architectures.
After going through a rabbit hole what I learned that this patch does is to allow time critical applications at top priority.
Most of popular linux distributions already have this patch applied in one form or another.
What I think it means for end user is that if applications use this part of linux kernel correctly, then they can speed up some core parts, be more responsive, and stable. But if it’s abused, it can end up slowing the whole system.
