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Wysocki (Intel)" Cc: rafael.j.wysocki@intel.com, Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , frederic@kernel.org, linux-pm@vger.kernel.org, LKML , regressions@lists.linux.dev References: <096b42fa-107f-450d-b3b1-03bcad3f1e04@oracle.com> <5f5cb821-92ae-4539-ae81-a43e33a7ded5@arm.com> <774c3a68-6a6b-4e2e-a347-03e36953b750@arm.com> <0b9b9c3d-8ba0-4329-9504-b9d33c627649@arm.com> <097f4855-eca1-414a-932c-107d9eee5088@broadcom.com> From: Thorsten Leemhuis Content-Language: de-DE, en-US In-Reply-To: <097f4855-eca1-414a-932c-107d9eee5088@broadcom.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-PPP-Message-ID: <179438885852.683699.2690732334273648782@mxe9fb.netcup.net> X-NC-CID: XD/K3O4gQ183UQRoZIs2OH3cLb2x+hy0xzzYw5B1Oui9uqVdcTc= On 11/6/26 00:59, Florian Fainelli wrote: > On 7/28/26 09:37, Christian Loehle wrote: >> Commit f4c31b07b136 ("sched: idle: Consolidate the handling of two >> special cases") changed the no-cpuidle-driver path to use the previous >> tick wakeup heuristic. >> >> Oracle reported a substantial sysbench regression on small OCI VM shapes >> with no cpuidle driver available. Reverting the commit recovered the lost >> performance. >> >> Restore the previous tick handling for the no-driver case while retaining >> the heuristic for the single-state cpuidle case. >> >> Fixes: f4c31b07b136 ("sched: idle: Consolidate the handling of two >> special cases") > [...] > > We also hit this issue after it got back ported into stable trees (5.15, > 6.1, etc.) and this is seen during a network throughput test. FWIW, a fix for the above-mentioned commit recently hit mainline, so I wonder if that might change anything: 96a494c9cfd8f4 ("sched/cputime: Don't account idle time twice after dyntick-idle") [v7.4-rc1] https://lore.kernel.org/all/20261005194010.168299-1-stian@itx.no/ Ciao, Thorsten