Hi~ In your case, typically C3 should map to CPU C6. Best Regards, Edward On Sun, Jun 21, 2009 at 5:20 PM, Mahmood Naderan<mahmood.nt@xxxxxxxxx> wrote: > I got more confused... In my first post if you see, BIOS reports C1, > C2 and C6. Even it does not support C3 (!), but here is the output of > "cat /proc/acpi/processor/CPU0/power": > > active state: C0 > max_cstate: C8 > bus master activity: 00000000 > maximum allowed latency: 2000000000 usec > states: > C1: type[C1] promotion[--] demotion[--] > latency[001] usage[00000063] duration[00000000000000000000] > C2: type[C2] promotion[--] demotion[--] > latency[001] usage[00017466] duration[00000000000014422985] > C3: type[C3] promotion[--] demotion[--] > latency[162] usage[00096196] duration[00000000000650582389] > > So I think something (BIOS or CPU or OS) is malfunctioning and does > not report correctly. > Now the big question is, will my system (a combination of CPU, BIOS > and OS) enter C3 (or even deeper states)? > > -------------------------- > *Mahmood Naderan* > > > > > On Sun, Jun 21, 2009 at 2:34 AM, Ananth Narayan > S<ananth.narayan@xxxxxxxxx> wrote: >> You could see it that way. The OS will use the C states exported by >> the BIOS. If C4/C5 are not exported, the OS will not even know that >> such states exist. If you query /proc/acpi/CPU*/power, you'll probably >> see just three C states listed (C1, C2, C3). Typically the last >> C-state (C3) in that will map to the lowest C-state supported by the >> processor. >> >> -- Ananth >> >> >> >> >> On Sat, Jun 20, 2009 at 8:46 AM, Mahmood Naderan<mahmood.nt@xxxxxxxxx> wrote: >>> Hi, >>> So if my understanding is correct, the BIOS does not allow the CPU to >>> enter C4 and C5 states. Right? >>> >>> -------------------------- >>> *Mahmood Naderan* >>> >>> >>> >>> >>> On Sat, Jun 20, 2009 at 7:56 PM, Ananth Narayan >>> S<ananth.narayan@xxxxxxxxx> wrote: >>>> Intel processors export a max supported c state value. But when it >>>> comes to c states, typically the one that provides max power savings >>>> is exported by the BIOS. The intermediate ones aren't. >>>> >>>> -- Ananth Narayan S. >>>> >>>> >>>> >>>> >>>> On Fri, Jun 19, 2009 at 10:07 AM, Mahmood Naderan<mahmood.nt@xxxxxxxxx> wrote: >>>>> Hi, >>>>> I have run powertop with root permission with both AC and batter powers. The >>>>> reported C_States are the same and strange: >>>>> >>>>> mahmood@magma:~$ sudo powertop >>>>> PowerTOP 1.11 (C) 2007, 2008 Intel Corporation >>>>> >>>>> Collecting data for 5 seconds >>>>> >>>>> Your CPU supports the following C-states : C1 C2 C3 C4 C5 C6 >>>>> Your BIOS reports the following C-states : C1 C2 C6 >>>>> >>>>> Where are C4 and C5? >>>>> >>>>> -------------------------- >>>>> *Mahmood Naderan* >>>>> -- >>>>> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in >>>>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>>>> >>>> >>> >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Best Regards, Edward -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
