Real-time version PREEMPT_RT

Locietta / xanmod-kernel-WSL2

Xanmod kernel for WSL2, built by clang with ThinLTO enabled. Build & Release are automated by Github Action.

GNU General Public License v2.0

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Real-time version PREEMPT_RT #88

Open 4-FLOSS-Free-Libre-Open-Source-Software opened 22 hours ago

4-FLOSS-Free-Libre-Open-Source-Software commented 22 hours ago

Since mainline Linux Kernel 6.12 ships, PREEMPT_RT. No patching required anymore for real time kernel.

https://xanmod.org lists alongside LTS that we got already here, another branch

RT	Stable Real-time

Well the Xanmod is not 6.12 yet and the RT version equals LTS and is 6.6 currently.

A Locietta/xanmod-kernel-WSL2 fork, implemented it: https://github.com/taalojarvi/Stratosphere-Kernel-WSL2/commit/fe4ee5e121245f7687eb43e6304531fa3d762c64

Can we add another release, additional to LTS for RT version?

Andarwinux commented 22 hours ago

I doubt RT makes sense for WSL, no one is trying to use WSL2 as a pro-audio workstation or an IoT edge controller, and for other general use cases it just reduces performance.

By the way, if you enable RT, you will lose THP.

ref: https://lwn.net/Articles/938236 https://www.youtube.com/watch?v=7hwoJanE5-U

4-FLOSS-Free-Libre-Open-Source-Software commented 19 hours ago

By the way, if you enable RT, you will lose THP.

Thanks for hint, it also disables more flags according to Disabled CONFIG_ options, but which should not affect this WSL2 Kernel version negatively further than lacking THP for now, until THP realtime support fixed.

Several features are disabled by CONFIG_PREEMPT_RT=y because of incompatibility.

Disable Incompatible Options with PREEMPT_RT:

CONFIG_TRANSPARENT_HUGEPAGE: transparent huge page (THP) support; currently, it is disabled when PREEMPT_RT is chosen. Gleixner said that the problems with THP for realtime need to be fixed, "patches welcome". The realtime project has been focused on getting other things done, and has not tackled THP yet. There is no technical reason why the two cannot work together, they just do not right now.

taalojarvi commented 5 hours ago

Since mainline Linux Kernel 6.12 ships PREEMPT_RT. No patcing required anymore for real time kernel.

https://xanmod.org lists alongside LTS that we got already here, another branch RT Stable Real-time

Well the Xanmod is not 6.12 yet and the RT version equals LTS and is 6.6 currently.

An Locietta/xanmod-kernel-WSL2 fork, implemented it: taalojarvi@fe4ee5e

Can we add another release, additional to LTS for RT version?

Would it be a good idea to move from PREEMPT_VOLUNTARY to PREEMPT?

4-FLOSS-Free-Libre-Open-Source-Software commented 1 hour ago

I was testing this. Changes were pushed out of source. Apart from scheduler latency being very consistent, there wasn't any notable improvements.

But you were testing an < 6.12 Kernel Version or?