Date: Mon, 27 Jan 2020 03:11:04 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 234733] Setting CPU frequency with sysctl dev.cpu.0.fr slows a Ryzen 2700X down Message-ID: <bug-234733-227-KMnIWeBZW0@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-234733-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=234733 --- Comment #10 from sigsys@gmail.com --- (In reply to Conrad Meyer from comment #9) It's showing some interesting behavior I think. The last 3 bits of 0xc0010061 and 0xc0010062 go up but don't go down. And they go up together. At boot: # cpucontrol -m '0xc0010061' /dev/cpuctl0 MSR 0xc0010061: 0x00000000 0x00000020 # cpucontrol -m '0xc0010062' /dev/cpuctl0 MSR 0xc0010062: 0x00000000 0x00000000 After dev.cpu.0.freq=3200 (max): # cpucontrol -m '0xc0010061' /dev/cpuctl0 MSR 0xc0010061: 0x00000000 0x00000020 # cpucontrol -m '0xc0010062' /dev/cpuctl0 MSR 0xc0010062: 0x00000000 0x00000000 (No change there.) After dev.cpu.0.freq=2800: # cpucontrol -m '0xc0010061' /dev/cpuctl0 MSR 0xc0010061: 0x00000000 0x00000021 # cpucontrol -m '0xc0010062' /dev/cpuctl0 MSR 0xc0010062: 0x00000000 0x00000001 After dev.cpu.0.freq=1500: # cpucontrol -m '0xc0010061' /dev/cpuctl0 MSR 0xc0010061: 0x00000000 0x00000022 # cpucontrol -m '0xc0010062' /dev/cpuctl0 MSR 0xc0010062: 0x00000000 0x00000002 After dev.cpu.0.freq=3200 (trying to set it back to max): # cpucontrol -m '0xc0010061' /dev/cpuctl0 MSR 0xc0010061: 0x00000000 0x00000022 # cpucontrol -m '0xc0010062' /dev/cpuctl0 MSR 0xc0010062: 0x00000000 0x00000002 And performance is still as if it were at 1500. After cpucontrol -m '0xc0010062=0x0' on all CPUs: # cpucontrol -m '0xc0010061' /dev/cpuctl0 MSR 0xc0010061: 0x00000000 0x00000020 # cpucontrol -m '0xc0010062' /dev/cpuctl0 MSR 0xc0010062: 0x00000000 0x00000000 And now performance is back to what it was at 3200! I didn't manually try to reset 0xc0010061, it already reverted back to its initial value after changing 0xc0010062. -- You are receiving this mail because: You are the assignee for the bug.help
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