From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andras.Horvath@cern.ch Subject: Intel Clovertown vs. frequency scaling Date: Thu, 11 Oct 2007 17:06:33 +0200 Message-ID: <20071011150633.GL6058@cern.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: cpufreq-bounces@lists.linux.org.uk Errors-To: cpufreq-bounces+glkc-cpufreq=m.gmane.org+glkc-cpufreq=m.gmane.org@lists.linux.org.uk To: cpufreq@lists.linux.org.uk Hi, I have a number of Clovertown (intel quadcore) machines and, even with the latest 2.6.23, it seems to me that frequency scaling is not supported (e.g. the /sys/devices/system/cpu/cpu0/cpufreq/* stuff does not appear even though CONFIG_X86_SPEEDSTEP_CENTRINO is "y"). Is that as expected? This is what the CPU (one core in one of the two sockets) looks like: # head -24 /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Xeon(R) CPU L5335 @ 2.00GHz stepping : 11 cpu MHz : 1995.105 cache size : 4096 KB physical id : 0 siblings : 4 core id : 0 cpu cores : 4 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni monitor ds_cpl vmx tm2 ssse3 cx16 xtpr dca lahf_lm bogomips : 3994.09 clflush size : 64 also: # cat /proc/acpi/processor/CPU0/info processor id: 0 acpi id: 0 bus mastering control: no power management: yes throttling control: yes limit interface: yes # cat /proc/acpi/processor/CPU0/power active state: C2 max_cstate: C8 bus master activity: 00000000 maximum allowed latency: 20000 usec states: C1: type[C1] promotion[C2] demotion[--] latency[020] usage[00003940] duration[00000000000000000000] *C2: type[C2] promotion[--] demotion[C1] latency[040] usage[00013668] duration[00000000000359543325] FWIW, I also have some other Core-based (Woodcrest, Intel L5160) systems and cpufreq works fine there. Any help or insight would be appreciated. (I'm experimenting with ways to lower the average power consumption of a large number of servers, working my way through http://www.lesswatts.org etc. I'm willing to patch kernels, run tests, and I have proper power meters to check the results.) Andras