Microcode version check vs code update

Posted Apr 6, 2024 22:05 UTC (Sat) by akostadinov (guest, #48510)
In reply to: Microcode version check vs code update by bof
Parent article: Stable kernels to address Zenbleed released

Hi. Did you observe a positive performance improvement?

After some fiddling I managed to install a new microcode on a Ryzen 5 3600 but I actually see a slight (1%-1.5%) negative performance effect on multi-thread performance (according to geekbench).

It was tricky to find my CPUID, funnily at the end I just looked it up on http://instlatx64.atw.hu/

Afterwards downloading a new microcode from CPUMicrocodes [1] and merging it into `/usr/lib/firmware/amd-ucode/microcode_amd_fam17h.bin` with amd-ucodegen and amd_ucode_info was more straightforward.

$ sudo dmesg | grep -i microcode
[ 1.125508] microcode: Current revision: 0x08701033
[ 1.125510] microcode: Updated early from: 0x08701030

I wrote a blog to describe how exactly to update [2].

[1] https://github.com/platomav/CPUMicrocodes/tree/master/AMD
[2] https://rboci.blogspot.com/2024/04/zenbleed-microcode-upd...