hello, I have some questions about scailing CPU frequency. I want to create an environment with 1 higher CPU frequency and 3 lower CPU frequency on Fedora system(linux kernel 2.6.32) with acpi-cpufreq driver (Intel Core i7-920 Processor). **************************************************************************************************** this is the cpufreq-info report: cpufrequtils 007: cpufreq-info (C) Dominik Brodowski 2004-2009 Report errors and bugs to cpufreq@xxxxxxxxxxxxxxx, please. analyzing CPU 0: driver: acpi-cpufreq CPUs which run at the same hardware frequency: 0 1 2 3 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: 10.0 us. hardware limits: 1.60 GHz - 2.67 GHz available frequency steps: 2.67 GHz, 2.53 GHz, 2.40 GHz, 2.27 GHz, 2.13 GHz, 2.00 GHz, 1.87 GHz, 1.73 GHz, 1.60 GHz available cpufreq governors: ondemand, userspace, performance current policy: frequency should be within 1.60 GHz and 2.67 GHz. The governor "userspace" may decide which speed to use within this range. current CPU frequency is 2.67 GHz (asserted by call to hardware). analyzing CPU 1: driver: acpi-cpufreq CPUs which run at the same hardware frequency: 0 1 2 3 CPUs which need to have their frequency coordinated by software: 1 maximum transition latency: 10.0 us. hardware limits: 1.60 GHz - 2.67 GHz available frequency steps: 2.67 GHz, 2.53 GHz, 2.40 GHz, 2.27 GHz, 2.13 GHz, 2.00 GHz, 1.87 GHz, 1.73 GHz, 1.60 GHz available cpufreq governors: ondemand, userspace, performance current policy: frequency should be within 1.60 GHz and 2.67 GHz. The governor "userspace" may decide which speed to use within this range. current CPU frequency is 2.67 GHz (asserted by call to hardware). analyzing CPU 2: driver: acpi-cpufreq CPUs which run at the same hardware frequency: 0 1 2 3 CPUs which need to have their frequency coordinated by software: 2 maximum transition latency: 10.0 us. hardware limits: 1.60 GHz - 2.67 GHz available frequency steps: 2.67 GHz, 2.53 GHz, 2.40 GHz, 2.27 GHz, 2.13 GHz, 2.00 GHz, 1.87 GHz, 1.73 GHz, 1.60 GHz available cpufreq governors: ondemand, userspace, performance current policy: frequency should be within 1.60 GHz and 2.67 GHz. The governor "userspace" may decide which speed to use within this range. current CPU frequency is 2.67 GHz (asserted by call to hardware). analyzing CPU 3: driver: acpi-cpufreq CPUs which run at the same hardware frequency: 0 1 2 3 CPUs which need to have their frequency coordinated by software: 3 maximum transition latency: 10.0 us. hardware limits: 1.60 GHz - 2.67 GHz available frequency steps: 2.67 GHz, 2.53 GHz, 2.40 GHz, 2.27 GHz, 2.13 GHz, 2.00 GHz, 1.87 GHz, 1.73 GHz, 1.60 GHz available cpufreq governors: ondemand, userspace, performance current policy: frequency should be within 1.60 GHz and 2.67 GHz. The governor "userspace" may decide which speed to use within this range. current CPU frequency is 2.67 GHz (asserted by call to hardware). **************************************************************************************************** When I want to create the environment I want, the lower freq. always sync with the higher freq. It means that as long as one CPU frequency is higher, the rest lower freq will adjust to the higher freq. even I set them to the lower freq. >From the cpufreq-info report, it seems they are using hardware coordination, not software coordination. I saw some other articles talking about we can choose which coordination to use. Do you know how to setting to software coordination, even if the power do not save any consumption is ok. I want the different speed of CPU for experiment. Thanks for your listening! BR, Sabrina -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
