Thinking about trying out the new preemption model:

"make xconfig" screenshot:
https://imgur.com/OvlXmF5

From kernel/Kconfig.preempt:

config PREEMPT_RT
bool "Fully Preemptible Kernel (Real-Time)"
depends on EXPERT && ARCH_SUPPORTS_RT
select PREEMPTION
help
This option turns the kernel into a real-time kernel by replacing
various locking primitives (spinlocks, rwlocks, etc.) with
preemptible priority-inheritance aware variants, enforcing
interrupt threading and introducing mechanisms to break up long
non-preemptible sections. This makes the kernel, except for very
low level and critical code paths (entry code, scheduler, low
level interrupt handling) fully preemptible and brings most
execution contexts under scheduler control.

Select this if you are building a kernel for systems which
require real-time guarantees.

endchoice
_ _ _ _ _ _ _

I currently use the standard preemption:
Linux lm 6.12.0 #1 SMP PREEMPT_DYNAMIC Tue Nov 19 11:11:40 PST 2024
x86_64 x86_64 x86_64 GNU/Linux

Just decided in the name of Science(!), I gotta try this, and see
what it does to running graphical games, such as Elite Dangerous.
Wish me luck!

--
-v System76 Thelio Mega v1.1 x86_64 NVIDIA RTX 3090 Ti
OS: Linux 6.12.0 Release: Mint 21.3 Mem: 258G
"The Majority is never right unless it includes me."

On 22 Nov 2024 05:29:39 GMT, vallor wrote:

> Just decided in the name of Science(!), I gotta try this, and see what
> it does to running graphical games, such as Elite Dangerous. Wish me
> luck!

I’m going to stick my neck out and say this isn’t going to help.
PREEMPT_RT is for hard realtime, like pro audio/music processing where you
have to send/receive so many bytes every millisecond, otherwise quality
noticeably suffers. Things that are limited by human reflexes, like video
games, likely will not benefit. Human reflexes are measured in tenths of a
second, which is plenty of time to get things done in non-realtime
kernels.

On Fri, 22 Nov 2024 06:32:25 -0000 (UTC), Lawrence D'Oliveiro
<ldo@nz.invalid> wrote in <vhp8hp$12m83$1@dont-email.me>:

> On 22 Nov 2024 05:29:39 GMT, vallor wrote:
>
>> Just decided in the name of Science(!), I gotta try this, and see what
>> it does to running graphical games, such as Elite Dangerous. Wish me
>> luck!
>
> I’m going to stick my neck out and say this isn’t going to help.
> PREEMPT_RT is for hard realtime, like pro audio/music processing where you
> have to send/receive so many bytes every millisecond, otherwise quality
> noticeably suffers. Things that are limited by human reflexes, like video
> games, likely will not benefit. Human reflexes are measured in tenths of a
> second, which is plenty of time to get things done in non-realtime
> kernels.

I was more expecting (perhaps) smoother video and audio when
the system was under load.

We'll have to see, I couldn't go through with it:

dkms build of nvidia modules threw warnings about unknown
scheduler and mutex symbols. Also, same for some Thelio modules.

When the NVIDIA drivers catch up, I'll try it...or I might try
nouveau, though I'm reluctant to fight with that at this late
hour. (I think all I need is the Vulkan extensions from Mesa,
since my game uses DXVK -- but those extensions are in pretty
rough shape, so I've read.)

--
-v System76 Thelio Mega v1.1 x86_64 NVIDIA RTX 3090 Ti
OS: Linux 6.12.0 Release: Mint 21.3 Mem: 258G
"If it walks out of your refrigerator, LET IT GO !!"