Messages in this thread | | | Date | Fri, 23 Jul 2004 20:54:39 +0200 | From | Riccardo Vestrini <> | Subject | is it really better speedstep-ich vs. p4-clockmod cpufreq driver? |
| |
it seems that speedstep-ich and acpi cpufreq driver have only two usable clock frequencies, while p4-clockmod has eight my cpu is: Intel Mobile Intel(R) Pentium(R) 4 CPU 3.06GHz stepping 09
last 2.6 kernel I tried (2.6.7) has introduced a warning while loading p4-clockmod module:
p4-clockmod: P4/Xeon(TM) CPU On-Demand Clock Modulation available p4-clockmod: Warning: Pentium 4-M detected. The speedstep-ich or acpi cpufreq modules offer voltage scaling in addition of frequency scaling. You should use either one instead of p4-clockmod, if possible.
so I immediatly switched to speedstep-ich discovering that: $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies 3066590 1599960
while with p4-clockmod I have: $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies 383323 766647 1149971 1533295 1916618 2299942 2683266 3066590
using acpi driver gives a message: cpufreq: CPU0 - ACPI performance management activated. cpufreq: P0: 3059 MHz, 24000 mW, 100 uS cpufreq: *P1: 1596 MHz, 12000 mW, 100 uS but: $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies 3059000 1596000
i do not know what driver is supposed to be better and why speedstep-ich driver has only two frequencies
thank you
--
Riccardo Vestrini <riccardov@sssup.it>
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |