
Cachy: Out of tree Linux scheduler improving CPU cache usage - karma_daemon
https://github.com/hamadmarri/cachy-sched
======
rurban
His previous attempt on the same policy was
[https://github.com/hamadmarri/popcorn](https://github.com/hamadmarri/popcorn)

This new one looks simpler and a bit better.

------
gravypod
It would be interesting to see how this scales with cores/threads. Current gen
CPUs have ~128 threads per socket and you can find hardware that is quad
socket. I've seen some systems with <512 concurrent processes running. In
those use cases would this patch have the effect of pinning each process to a
single thread (ignoring io/other sleep states)? Would the performance benefits
of this patch scale super-linearly against thread count?

~~~
zamadatix
"No support for NUMA, NUMA must be disabled." means you probably don't want to
use this with a multi socket system. It looks like idle is enqueued when no
tasks are active and (in the case where hardware threads > requested threads)
for something where the task is always busy it'd stay on the current core
(though that's not particularly unique to this scheduler).

Also worth noting "This scheduler is designed for desktop usage since it is
about responsiveness. It may be not bad for servers.".

------
LinuxBender
Very nice! I hope this is considered for merge into the kernel as an optional
scheduler.

