Re: CPUs with variable speed clocks ?
Thomas Charron writes: > Aye, the Intel Core 2 Duo's have 'Advanced Intel Speedstep' capabilities. > The clock can be dynamically modified by multipliers, I believe up to 8 > different speeds. I'll give you more info as I investigate it, as the > kernel I built last night I enabled for it. > > Thomas > speedstep and powernow work fine under linux, but usually require a kernel that knows about your sepecific cpu. Auto-detection isn't fully baked, and I have to load the appropriate modules, but it works fine after that. in my case: * cpufreq_userspace * powernow-k8 On my X2 I get 4 speed choices and both cores need to run the same speed: pmg-alliance:10002:/sys/devices/system/cpu/cpu0/cpufreq/ cat scaling_available_frequencies 220 200 180 100 pmg-alliance:10003:/sys/devices/system/cpu/cpu0/cpufreq/ cat scaling_cur_freq 100 pmg-alliance:10004:/sys/devices/system/cpu/cpu0/cpufreq/ cat affected_cpus 0 1 I'd recomend powernowd (v0.97) using the userspace governor, but there are other choices out there. -- Dave ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: CPUs with variable speed clocks ?
Aye, the Intel Core 2 Duo's have 'Advanced Intel Speedstep' capabilities. The clock can be dynamically modified by multipliers, I believe up to 8 different speeds. I'll give you more info as I investigate it, as the kernel I built last night I enabled for it. ThomasOn 11/3/06, Paul Lussier <[EMAIL PROTECTED]> wrote: Has anyone here encountered such a beast?I ran into a discussion on another mailing list, and that was thefirst I had heard about CPUs with variable speed clocks. Does anyoneknow how you muck with these under Linux? I would guess that there's some kernel parameter you can toggle to (en|dis)able this feature.Would there be a /proc thingy you can 'echo 1' into like some of theiptables features as well?--Seeya,Paul___ gnhlug-discuss mailing listgnhlug-discuss@mail.gnhlug.orghttp://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/ ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: CPUs with variable speed clocks ?
On 11/3/06, Paul Lussier <[EMAIL PROTECTED]> wrote: Has anyone here encountered such a beast?I'd centure to say this is the cpuspeed/cpufreq facility. As far as I know, many distros have this already and load the appropriate modules is one is available for the CPU (well, ok, at least some of the Fedora Core distros do this). See http://www.carlthompson.net/Software/CPUSpeed for more.-Shawn ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: CPUs with variable speed clocks ?
On 11/3/06, Paul Lussier <[EMAIL PROTECTED]> wrote: Has anyone here encountered such a beast? Sure. They've been standard issue on laptops for years. The Intel brand name is "SpeedStep"; for AMD it is "PowerNow. A Google for "Linux SpeedStep PowerNow" appears to be promising. Modern processors may also include the capability to "turn off" or "slow down" parts that aren't being used right as much. For example, if nothing is hitting the FPU on a Pentium 4, that happens. I believe that is all "automatic" at the hardware level, though. Further back, Linux has long had a feature where, if there are no processes ready to run (i.e., all blocked on I/O), the scheduler issues a "HLT" instruction to the CPU, which in turn knows to reduce its operations. I discovered that my old 300 MHz AMD K6 ran measurably cooler with Linux than Windows 98! -- Ben ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: CPUs with variable speed clocks ?
On November 03, 2006, Paul Lussier sent me the following: > Has anyone here encountered such a beast? > > I ran into a discussion on another mailing list, and that was the > first I had heard about CPUs with variable speed clocks. Does anyone > know how you muck with these under Linux? I would guess that there's > some kernel parameter you can toggle to (en|dis)able this feature. > Would there be a /proc thingy you can 'echo 1' into like some of the > iptables features as well? I think it's a fairly common feature among laptop CPUs. I know my Pentium 3-M laptop had two clock settings, 1.13Ghz and 733Mhz or thereabouts. Check out the CPUfreq options in the kernel. Supported frequency scaling CPUs: http://www.kernel.org/pub/linux/utils/kernel/cpufreq/hardware.html -- Chip Marshall <[EMAIL PROTECTED]> http://kyzoku.2bithacker.net/ GCM/IT d+(-) s+:++ a25>? C++ UB$ P+++$ L- E--- W++ N@ o K- w O M+ V-- PS+ PE Y+ PGP++ t+@ R@ tv@ b++@ DI D+(-) G++ e>++ h>++ r-- y? signature.asc Description: PGP signature ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
CPUs with variable speed clocks ?
Has anyone here encountered such a beast? I ran into a discussion on another mailing list, and that was the first I had heard about CPUs with variable speed clocks. Does anyone know how you muck with these under Linux? I would guess that there's some kernel parameter you can toggle to (en|dis)able this feature. Would there be a /proc thingy you can 'echo 1' into like some of the iptables features as well? -- Seeya, Paul ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
