linux-kernel - Re: [PATCH v3 0/2] cpufreq/amd-pstate: Set initial min_freq to lowest_nonlinear

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <62f0402c-89a4-4ca8-b443-fbc9cc3b2055@amd.com>
Date: Sun, 8 Dec 2024 10:35:16 -0600
From: Mario Limonciello <mario.limonciello@....com>
To: Hanabishi <i.r.e.c.c.a.k.u.n+kernel.org@...il.com>,
 Dhananjay Ugwekar <Dhananjay.Ugwekar@....com>, gautham.shenoy@....com,
 perry.yuan@....com, rafael@...nel.org, viresh.kumar@...aro.org
Cc: linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 0/2] cpufreq/amd-pstate: Set initial min_freq to
 lowest_nonlinear_freq

On 12/8/2024 01:54, Hanabishi wrote:
> Hello. Maybe I'm too late on this, but I have some concerns.
> 
> On 10/17/24 05:39, Dhananjay Ugwekar wrote:
>> In other systems, power consumption has increased but so has the
>> throughput/watt.
> 
> I just want to bring up the fact that this change affects all governors. 
> It sounds good for the performance governor, but not so much for the 
> powersave governor.
> 
> So the question is: don't we want the lowest power consumption possible 
> in the powersave mode? Even if it means decreased efficiency. Powersave 
> by definition supposed to make battery last as long as possible no 
> matter what, isn't it?
> 

No, the powersave governor isn't a one stop shop to bring everything to 
longest battery.

By your argument we should set the EPP to "power" by default and "boost" 
to off by default when the powersave governor is enacted?

All of those are far too aggressive for a default behavior.  Setting the 
lowest nonlinear frequency as the default lowest scaling frequency is 
about having a good default that balances responsiveness, battery life 
and performance.

Like all knobs anyone that doesn't agree with it can of course modify it 
from sysfs.