For the recently launched AMD [1]EPYC 9005 series "Turin" processors there is good support out-of-the-box running on the likes of Linux 6.8 as found with Ubuntu 24.04 LTS. The one exception is if wanting to engage CPU power monitoring you need a RAPL/PowerCap patch that was just upstreamed in v6.12. But what about using a newer kernel for greater performance in light of all the upstream optimizations to the kernel in general? Here are some Linux 6.8 vs. 6.11 vs. 6.12 kernel benchmarks on a dual AMD EPYC 9755 server.

Linux 6.8 as shipped by Ubuntu 24.04 LTS is in good shape for 5th Gen AMD EPYC, but of course, I'm always excited about what's coming down the pipe in future kernel versions... There's been many great changes upstreamed to the kernel since that point earlier in the year. [2]Linux 6.11 is the latest stable kernel version right now and what's found in the (non-LTS) Ubuntu 24.10. [3]Linux 6.11 has some great features while [4]Linux 6.12 is in development for releasing in November. Linux 6.12 is expected to be this year's Long Term Support (LTS) kernel version and [5]it's super heavy on new features from real-time "PREEMPT_RT" to sched_ext to new hardware additions and much more.

[6]

So for some quick benchmarks today, here are some numbers I recently carried out comparing Linux 6.8 (Ubuntu 24.04 stock kernel) to Linux 6.11 upstream stable and then the Linux 6.12 Git development state as of last week.

The same AMD EPYC 9755 2P server was used for all these kernel benchmarks without any modifications to the software/hardware besides swapping out the kernel version employed. The 6.11 and 6.12 Git kernel builds were following the same mainline PPA kernel configuration.

For most workloads there were no big changes in performance going from Linux 6.8 earlier this year to Linux 6.12 currently under development...

Many of the workloads were only subtly faster on Linux 6.11~6.12 than Linux 6.8.

But for some benchmarks particularly those that are very kernel focused, there were indeed gains to find when upgrading from Linux 6.8 to Linux 6.11/6.12.

In many of the larger, real-world workloads there were minimal to small changes while in more of the micro-benchmarks and other focused areas there were some nice gains observed with Linux 6.11/6.12. With Linux 6.12 expected to be this year's LTS kernel version, it will find use by hyperscalers and other large organizations that maintain their own distributions / customized software stacks and tend to jump between the LTS kernel versions. Linux 6.12 overall is looking quite nice for 5th Gen AMD EPYC.



[1] https://www.phoronix.com/search/EPYC+9005

[2] https://www.phoronix.com/search/Linux+6.11

[3] https://www.phoronix.com/review/linux-611-features

[4] https://www.phoronix.com/search/Linux+6.12

[5] https://www.phoronix.com/review/linux-612-features

[6] https://www.phoronix.com/image-viewer.php?id=2024&image=linux_612_epyc_lrg