[monocasa]

It's about measuring jitter caused by the OS. When you have a large message passing system like you see in HPC environments, delays in processing exactly the right messages add up to huge failures of utilization because of the dependency graph of work to be done. In the past I had even seen national labs write their own Linux syscall compatible kernels in order to combat jitter. For example: https://github.com/HobbesOSR/kitten

[guenthert]

Afaik (Linux compatible) Lightweight kernels (LWK) have been used in the past in lieu of Linux in (single application) HPC scenarios in order to reduce context switching and consequential cache misses and TLB thrashing.

I wouldn't know why 'the right message' needs to be processed in a HPC application (as opposed to real time applications). Where can I learn more about such?