From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CD84029438 for ; Thu, 18 Jan 2024 19:48:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705607306; cv=none; b=k6kjJaaxiY4AnBoJ4KlPCIax8sQPJ3Yy+2k6OH3vDenYhHaHdNujSCVqhxK6vEHzR5LQmkIx2ne1PwjGnjUk8kBFfiddVGU2QdcTuIe49n1xgkkMjR/xPpL9nknIzxoACnk8aDzQnyakqfr+ZTBhmV2kZ+X6x3wMYtkvoDJEZtk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705607306; c=relaxed/simple; bh=ltO/FmZ5fiMQCyD30w07gk/KM49R+euyRoJsqpMCVP8=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: Content-Type:MIME-Version; b=dJGLHNTmfhisxpI9Ms3Xx6zfMcJ/+EA+iJN+GoRzEOxt5bKBmj6ttONK6wOEr6sgpw6JPm9alQLpqunipEKaLhJpMJG92FFhnpenz97IjKy30Jylx6WN+tB8LnjYfn1sfM8d1HmvsEAxEbtxPg2dRvxrGhIuelC/tcjrOATGMCM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AUXiuaST; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="AUXiuaST" Received: by smtp.kernel.org (Postfix) with ESMTPS id 5E3BEC433A6 for ; Thu, 18 Jan 2024 19:48:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705607305; bh=ltO/FmZ5fiMQCyD30w07gk/KM49R+euyRoJsqpMCVP8=; h=From:To:Subject:Date:In-Reply-To:References:From; b=AUXiuaSTgjNbOLlaP61g4qqcuHnpW0PAdZSwx5pGEk/WH3r0ZENaNyII6asT7kQtD iKLoZt0oVBNM69zMQXMgzIvDgTp+EfCzLcV/vBpqSqFeNgP/KHbk/h5GSnALD3aNSS lRJ87pdkZoFMhkgq0x0LhAB6PSmYV7e0anREyvQolni5zfx8CY6bSk4qMHgUNs9Spe 2x73d1H0NeLj2f8zeIIAgkvzQ+Fx1Igk1hl6YIs7+f3mHrOMzN6K6K0DxPdMMRD6xh rdHLSIvYxVmCiYqq1mSaNBR2wzHlVwJE/5/V8Q2374UfA/LQgr8kKjEbKa9PxBk/+E km45c0Aw8jC/w== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id 4327DC53BD3; Thu, 18 Jan 2024 19:48:25 +0000 (UTC) From: bugzilla-daemon@kernel.org To: linux-pm@vger.kernel.org Subject: [Bug 217931] amd-pstate lacks crucial features: CPU frequency and boost control Date: Thu, 18 Jan 2024 19:48:24 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Power Management X-Bugzilla-Component: cpufreq X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: high X-Bugzilla-Who: haunma@keteu.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: linux-pm@vger.kernel.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 https://bugzilla.kernel.org/show_bug.cgi?id=3D217931 --- Comment #22 from Mark Haun (haunma@keteu.org) --- I repeated Artem's test on 6.7.0-rc6 (Void Linux with custom kernel---a bit old, sorry). My energy performance preference is set to "power". I think = I am seeing roughly what Pedro describes. Writing twice to scaling_max_freq is definitely doing something, at least if we believe the numbers reported by = htop or cpupower. Usually I cannot keep all of my cores (7840U) at 400 MHz; the active ones are habitually between 1-3 GHz. After following the above reci= pe, the active cores seem limited to ~544 MHz instead. (Although, since the amd-pstate-epp driver reputedly does not allow setting limits at all, I suppose we should consider the possibility that these repo= rted numbers are incorrect ;) It would sure be nice to have the non-determinism (i.e. bugs) ironed out of= the driver first, then consider supporting scaling_max_frequency. I am actually open to the idea---in principle---that the EPP stuff obsoletes max_frequenc= y, but I have to say, the entire scale is still biased too far towards performance. There ought to be a way for the user to basically tell the sy= stem "POWER POWER POWER above all, and I really mean it!!" but as it stands, the furthest that we are allowed to push things is still fairly weak: any core with the slightest activity is immediately boosted way up, so even an "idle" system constantly has a few cores way above idle speed. This might be why folks are asking for a frequency cap. Why isn't EPP more of a logarithmic scale, where both ends of the scale are so ridiculously overkill that most people will want a setting closer to the middle? *That* is how it should be designed. --=20 You may reply to this email to add a comment. You are receiving this mail because: You are the assignee for the bug.=