6.9 is going to be released soon, feel free to test!

Hi together,

The 6.9 kernel will be next week released and we are testing internally our 6.9 Release since a while and it is looking in a really good place.

Here is a little list of interesting changes in the main 6.9 Kernel:

  • P-State Prefferred Core is officially merged
  • New Hardware Monitor Support for AIOs - NZXT and ASUS
  • The old NTFS Driver got finally dropped
  • Improvements to bcachefs and a lot of fixes
  • Performance Optimization for BTRFS
  • Intel Metor Lake will have a better performance

CachyOS Kernel Changes


  • AES-XTS will now use instructions dynamically, this provides depending on the CPU up to 150% Performance improvement on Zen4 for example
  • AMD-Pstate Fixes and Enhancements
  • AMD-Pstate CPB Boost (Disabling Boost via sysfs or kernel cmdline)
  • BBR3 Support
  • Improvement on the block driver
  • Fixes for VRR on AMD, which should work now perfectly fine
  • uksmd support
  • NTSync support
  • ZSTD 1.5.6 API patched for better zstd performance


  • sched-ext has now cpufreq handling support and got integrated into scx_lavd
  • Improvement for sched-ext since its now able to use the latest bpf features, this results into a better performance for scx schedulers
  • scx_rusty got massively improved for interactivity

Testing the Kernel

You can simply install the linux-cachyos-rc kernel with following commands or via the kernel manager:

sudo pacman -Sy linux-cachyos-rc linux-cachyos-rc-headers

The ZFS and NVIDIA Module is compatible with the 6.9 Kernel.


If you find any bugs in this release, please let us know and try to identify the issue.


Just to report:

I have 100% been on linux-cachyos 6.9 since rc1. On zen4,full amd. Doing heavy video production, AI, gaming, etc… everything.

Everything has been rock stable since rc1. This kernel is ready for shipping, on my system.

Amazing job with the great patchset, including the updated zstd.


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We have pushed a little update, which contains fixes for NTSync and amd-pstate.
The aes-gcm algorithm got also a patch and can be now up to 100% faster, which is an awesome enhancements, thanks to Eric Bigger from Google.

This should be now the final version, which will also land into 6.9 Stable.

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Today the option to switch the energy performance profile in the KDE tray doesn’t work anymore. It says “not available”.

This is with 6.9.0-rc7-5-cachyos-rc-lto (v4). On zen4.

It has never happened before and I think it was caused by the last kernel update.

Thanks, I’ll check it later.

I could reproduce the issue and will look solving it tomorrow.
Its really weird, since all required informations are available, but well.

I think we will revert for now to an older branch for the amd-pstate, until the problem is solved.
Thanks for reporting.

It will be fixed in the final 6.9 Kernel.
We maybe will run into, that amd-pstate=active is as default used when booting, but power profiles daemon is working then.

Ill let you know, as soon my testing is done.

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It’s fine now in the final release. Thanks!

WOW! I just tested 6.9 CachyOS for first time for around 2 hours so far and compared 3 games to Nobara 39 (6.8.2 though):
Alan Wake 2 is 5 to 6 FPS faster! Starfield is 8 to 9 FPS faster! Remnant 2 is same performance!
And 1 game to Windows 7 (:D):
Outer Wilds is 30 FPS faster!
Really interesting!
Thank you CachyOS team!

There is a problem with Task Manager: menus don’t pop out when left clicked (right click works fine):
EDIT: nvm fixed after reboot!
EDIT2: not fixed lol (it seems it bugs after Firefox is launched)

Thats a Plasma bug and also noted in our Wiki at the How to install pae.
You just need to go shortly in x11 and then again wayland…


After upgrading two days ago to 6.9, first with pacman -Syu and after doing a fresh install from last released iso, my system (ryzen 3600x) becomes very sluggish. I think the problem is due to CPU freq stuck at 533 Mhz according to cpupower:

cpupower frequency-info
analyzing CPU 6:
  driver: acpi-cpufreq
  CPUs which run at the same hardware frequency: 6
  CPUs which need to have their frequency coordinated by software: 6
  maximum transition latency:  Cannot determine or is not supported.
  hardware limits: 2.20 GHz - 4.41 GHz
  available frequency steps:  3.80 GHz, 2.80 GHz, 2.20 GHz
  available cpufreq governors: conservative ondemand userspace powersave performance schedutil
  current policy: frequency should be within 2.20 GHz and 3.80 GHz.
                  The governor "schedutil" may decide which speed to use
                  within this range.
  current CPU frequency: Unable to call hardware
  current CPU frequency: 553 MHz (asserted by call to kernel)
  boost state support:
    Supported: yes
    Active: no

no matter if I stress CPU with sudo stress --cpu 8 --timeout 60, CPU freq keeps at same value and CPU fan keeps very quiet too.

When booting system this message appears:

[xxxx...] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect

this message repeats once for each core of the CPU.

I have a default installation with kernel cachyos-v3/linux-cachyos 6.9.0-2 stable.

Any suggestion?



Thanks for the report! I will push soon a fix for this.
Actually the upstream amd-pstate patches seems to have heavy problems… on Zen2 and Zen3. On Zen4 (where I test is everything flawless).

Thanks for reporting.

Im compiling right now a 6.9 Kernel with a fix.
you can download it from here:

sudo pacman -U https://build.cachyos.org/kernel/linux-cachyos-6.9.0-3-x86_64_v3.pkg.tar.zst https://build.cachyos.org/kernel/linux-cachyos-headers-6.9.0-3-x86_64_v3.pkg.tar.zst


Thanks for your fast response @ptr1337 ,

Trying to install 6.9.0-3 as suggested, but it complains because linux-cachyos-nvidia is dependant on, (sorry I forgot to mention I was using and nvidia card)

I’ll wait until all dependencies are resolved.


Ive removed now mostly all amd-pstate patches and just kept the one, which are merged in upstream. The Kernel is compiling and should come soon into the repository.

Here on zen4 everything is working fine too.


working fine now in zen3 too.


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