APPLIED Re: [PATCH][SRU][OEM-5.14] Improve performance and idle power consumption for AMD CPUs
Timo Aaltonen
tjaalton at ubuntu.com
Mon Oct 25 15:36:39 UTC 2021
On 9.10.2021 5.07, Alex Hung wrote:
> BugLink: https://bugs.launchpad.net/bugs/1941893
>
> [Impact]
>
> This can improve AMD performance for all Zen or newer CPU which support C3 shares cache.
>
> [Fix]
>
> Its not necessary to flush the caches in software before entering C3.
>
> Empirical measurements show:
> 40-45% improvement in speedometer score.
> ~15% improvement in idle power.
>
> The patch is in linux-next (tag next-20211007) and can be found @ https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/arch/x86/kernel/acpi/cstate.c?id=a8fb40966f19ff81520d9ccf8f7e2b95201368b8
>
> [Test]
>
> This is requested by AMD.
>
> [Where problems could occur]
>
> Low risk. This only works on AMD Zen CPUs that supports this features. AMD
> tested it and provided estimated measurement results.
>
> Deepak Sharma (1):
> x86: ACPI: cstate: Optimize C3 entry on AMD CPUs
>
> arch/x86/kernel/acpi/cstate.c | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
applied to oem-5.14, thanks
--
t
More information about the kernel-team
mailing list