linux-kernelpreempt-rt

Is built PREEMPT_RT more pre-emptive than PREEMPT_DYNAMIC set on full?


I am curious if there is any difference functional wise of the pre-empting system between the the modes described in the title. I was looking at this page https://github.com/torvalds/linux/blob/master/kernel/Kconfig.preempt and ca't say for sure if there is a difference or not.

This article https://lwn.net/Articles/944686/ seems to suggest there is no difference...

How to tell ?


Solution

  • It all gets clearer when you take a closer look at the article and kernel config options you link:

    Therefore, running a kernel with PREEMPT_DYNAMIC set to full is roughly the same as running a kernel built with PREEMPT=y. PREEMPT_RT is more preemptive than "full" PREEMPT, but not available with PREEMPT_DYNAMIC.