From: David Vernet <void@manifault.com>
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: "Mario Limonciello" <mario.limonciello@amd.com>,
linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
"André Almeida" <andrealmeid@igalia.com>,
"Changwoo Min" <changwoo@igalia.com>,
"Huang Rui" <ray.huang@amd.com>,
"Perry Yuan" <perry.yuan@amd.com>,
"K Prateek Nayak" <kprateek.nayak@amd.com>
Subject: Re: [RFC PATCH 0/4] cpufreq/amd-pstate: Per-core EPP boost for recently-busy CPUs
Date: Tue, 28 Jul 2026 02:36:12 -0500 [thread overview]
Message-ID: <amhbUVVyl-a-pUKC@maniforge> (raw)
In-Reply-To: <20260728073150.54964-1-void@manifault.com>
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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)
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next prev parent reply other threads:[~2026-07-28 7:36 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-28 7:31 [RFC PATCH 0/4] cpufreq/amd-pstate: Per-core EPP boost for recently-busy CPUs David Vernet
2026-07-28 7:31 ` [RFC PATCH 1/4] cpufreq/amd-pstate: Document missing kernel-doc members David Vernet
2026-07-28 7:31 ` [RFC PATCH 2/4] cpufreq/amd-pstate: Update cppc_req_cached before writing the MSR David Vernet
2026-07-28 7:31 ` [RFC PATCH 3/4] cpufreq/amd-pstate: Add per-core EPP boost for recently-busy CPUs David Vernet
2026-07-28 7:31 ` [RFC PATCH 4/4] Documentation: amd-pstate: Document the epp_boost parameter David Vernet
2026-07-28 7:36 ` David Vernet [this message]
2026-07-28 14:17 ` [RFC PATCH 0/4] cpufreq/amd-pstate: Per-core EPP boost for recently-busy CPUs Christian Loehle
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