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[76.141.129.107]) by smtp.gmail.com with ESMTPSA id 46e09a7af769-7ee4f10b691sm11081714a34.5.2026.07.28.00.36.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Jul 2026 00:36:14 -0700 (PDT) Date: Tue, 28 Jul 2026 02:36:12 -0500 From: David Vernet To: "Rafael J. Wysocki" Cc: Mario Limonciello , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, =?utf-8?B?QW5kcsOp?= Almeida , Changwoo Min , Huang Rui , Perry Yuan , K Prateek Nayak Subject: Re: [RFC PATCH 0/4] cpufreq/amd-pstate: Per-core EPP boost for recently-busy CPUs Message-ID: References: <20260728073150.54964-1-void@manifault.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="ix75mscgt5z7z432" Content-Disposition: inline In-Reply-To: <20260728073150.54964-1-void@manifault.com> User-Agent: NeoMutt/20260105 --ix75mscgt5z7z432 Content-Type: text/plain; protected-headers=v1; charset=us-ascii Content-Disposition: inline Subject: Re: [RFC PATCH 0/4] cpufreq/amd-pstate: Per-core EPP boost for recently-busy CPUs MIME-Version: 1.0 On Tue, Jul 28, 2026 at 02:31:46AM -0500, David Vernet wrote: > In active (EPP) mode the platform autonomously picks the operating point > between min_perf and max_perf, biased by the EPP hint, and the kernel > only rewrites the CPPC request on policy or limit changes. A workload > dominated by one mostly-busy thread that takes frequent short sleeps > (common in gaming workloads, for example) can fare poorly under this > strategy. Each sleep decays the hardware's performance signal, causing > post-wakeup bursts to start at a low operating point and inflating tail > latency even though the CPU is essentially fully busy while work is ... Argh, sorry, got my aliases mixed up. +cc the rest of the AMD pstate driver maintainers (and removing Gautham) --ix75mscgt5z7z432 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRBxU1So5MTLwphjdFZ5LhpZcTzZAUCamhb7AAKCRBZ5LhpZcTz ZADsAP9HLR8AExgpm+XUCKPB1EiyPIZOj8S9wWPJqt1e8f3tQwEA2vOUwaJaTCrx c8jUm8pEIf8q/kQFB2HHJDnHUSNVLAU= =TZIx -----END PGP SIGNATURE----- --ix75mscgt5z7z432--