Date: Fri, 28 Dec 2018 09:22:15 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 234455] CPU frequency scaling fails for multiple cores Message-ID: <bug-234455-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=234455 Bug ID: 234455 Summary: CPU frequency scaling fails for multiple cores Product: Base System Version: 12.0-RELEASE Hardware: amd64 OS: Any Status: New Severity: Affects Some People Priority: --- Component: kern Assignee: bugs@FreeBSD.org Reporter: dfrg@xsmail.com An intel i5-8400 processor has 6 cores. On both FreeBSD 11.2 and 12.0-RELEASE frequency scaling via both powerd or explicit sysctl is broken unless all but one core is disabled via BIOS. # sysctl dev.cpu.0.freq_levels dev.cpu.0.freq_levels: 2801/65000 2800/65000 2700/61690 2500/55888 2400/52759 2200/47301 2100/44946 1900/39204 1800/37000 1700/34277 1500/29546 1400/27531 1200/22557 1100/20688 900/16549 800/14296 # sysctl dev.cpu.0.freq=2800 dev.cpu.0.freq: 800 -> 800 It appears cf_set_method() returns EPERM at sys/kern_cpu.c:287 and commenting out that conditional restores frequency scaling when multiple cores are enabled. Whilst this ugly local patch suffices its obviously not correct and I'm not sure how to proceed from here. -- You are receiving this mail because: You are the assignee for the bug.
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