Date: Wed, 09 Oct 2019 16:07:30 +0000 From: Koakuma <koachan@protonmail.com> To: freebsd-ppc <freebsd-ppc@freebsd.org> Subject: CPU frequency scaling doesn't work on Mac mini G4 Message-ID: <BUAw5HidTMMt7nvgX089wTXfeyeHgDMapLSBDeeOylWdA31J2U5iVPCSLSSwZtRI1us9uwp5ZjBw1sB8G9pRqH7Jon3WvNK9aZI2MVPkcTo=@protonmail.com>
next in thread | raw e-mail | index | archive | help
Hi, I've just noticed a strange behavior regarding frequency scaling on the Mac mini G4. When I tried to set the CPU frequency using powerd, it (and "sysctl dev.cpu.0.freq") reports that the frequency has been changed, yet a test using "openssl speed" shows similar performance between the two frequencies. Here's the result of running "openssl speed -evp chacha20" with "powerd -n maximum" (1416 MHz): type=09=0916 bytes=0964 bytes=09256 bytes=091024 bytes=098192 bytes=0916384= bytes chacha20=0940326.69k=0961947.78k=0970339.29k=0972921.32k=0973479.72k=097330= 7.48k And with "powerd -n minimum" (708 MHz): type=09=0916 bytes=0964 bytes=09256 bytes=091024 bytes=098192 bytes=0916384= bytes chacha20=0940314.57k=0962121.26k=0970303.44k=0972740.17k=0973468.76k=097352= 0.78k I expect that openssl would run slower when the CPU frequency is set to minimum, but that's not the case here. Is it a bug or did I use the wrong program to measure it? The system is a freshly-installed 12.0-RELEASE on the 1.4 GHz model.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?BUAw5HidTMMt7nvgX089wTXfeyeHgDMapLSBDeeOylWdA31J2U5iVPCSLSSwZtRI1us9uwp5ZjBw1sB8G9pRqH7Jon3WvNK9aZI2MVPkcTo=>