The kernel is great at doing its job for your task, providing unified access to hardware, filesystem, network, scheduling your code when you need to, … But can’t it all be done quietly please, because your application is sensitive to headaches and is having a hard time focusing?

Some workloads indeed need bare metal exclusive use of the CPUs without being disturbed by anything else: other tasks, interrupts, exceptions.

The kernel has learned to hide in the shadows through many mechanisms that have been integrated over the years and none of which can be picked up without their own specific cost. It’s always a tradeoff.

Let’s have a tour into these features and see what is left to be done.

Frédéric Weisbecker, SUSE