Date: Tue, 8 Apr 2003 01:59:22 -0500 From: Dan Nelson <dnelson@allantgroup.com> To: Tobias Roth <roth@iam.unibe.ch> Cc: freebsd-questions@freebsd.org Subject: Re: find out current CPU frequency Message-ID: <20030408065922.GB23131@dan.emsphone.com> In-Reply-To: <20030408064923.GA21535@speedy.unibe.ch> References: <20030407071722.GC4573@speedy.unibe.ch> <200304071247.13863.mlists@northglobe.com> <20030408064923.GA21535@speedy.unibe.ch>
next in thread | previous in thread | raw e-mail | index | archive | help
In the last episode (Apr 08), Tobias Roth said: > > > I would like to find out what the current CPU frequency is on my > > > laptop. I strongly suspect that my laptop, as well as many other > > > models, pretty much permanently run on degraded performance, even > > > when under full load. > > > > > > At the moment, I use both 4.8 and 5.0 Release with apm, but I plan > > > to upgrade tocurrent soon. > > > dmesg | grep CPU > > Isn't that good enough? Or do you mean after boot? > > no. that is the maximum frequency the cpu runs at, which is fixed. > with intels speedstep there is a possibility that the cpu runs at a > lower frequency than that, depending on the current load. > > the idea behind it is this: > high load -> high freq -> high power consumption, more fan activity > low load -> lower freq -> lower power consumption, less fan activity > > linprocfs for instance always shows a current cpu freq of > 1.1something GHZ on my 1.8GHz P4. however I have no idea how > representative that is. Check the results of "sysctl hw.acpi.cpu". If your motherboard supports it, you should see something like: hw.acpi.cpu.max_speed: 16 hw.acpi.cpu.current_speed: 16 hw.acpi.cpu.performance_speed: 16 hw.acpi.cpu.economy_speed: 8 max_speed is 100%; anything less sets the CPU sped proportionately slower. I have never tried to set hw.acpi.cpu.current_speed=0 :) -- Dan Nelson dnelson@allantgroup.com
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20030408065922.GB23131>