HEADS UP: Release schedule for 2006

martinko martinkov at pobox.sk
Sun Dec 18 11:46:54 PST 2005

Kevin Oberman wrote:

>>Date: Sat, 17 Dec 2005 18:14:01 +0100
>>From: martinko <martinkov at pobox.sk>
>>Kevin Oberman wrote:
>>>>Date: Fri, 16 Dec 2005 14:29:39 -0600
>>>>From: Craig Boston <craig at feniz.gank.org>
>>>>Sender: owner-freebsd-stable at freebsd.org
>>>>>-cpu0: <ACPI CPU (4 Cx states)> on acpi0
>>>>>+cpu0: <ACPI CPU> on acpi0
>>>>>Q: Guessing that's a formatting difference, rather then 6.x not recognizing 
>>>>>the states (sysctl hw.acpi.cpu.cx_supported confirms 4 states)
>>>>Not sure on this, but you're probably better off using EST anyway as I
>>>>think it gives you more control over the processor frequency.
>>>No. There is no conflict between Cx states and EST. Cx states specifies
>>>how deeply the CPU will sleep when idle. EST controls processor speed
>>>and voltage. In most cases, your REALLY want to use both of these. They
>>>are very significant in saving power. (Of course, USB tends to limit the
>>>effectiveness of Cx states. I need to run without USB to get really good
>>>battery life and to make suspend (S3) really ut power drain.
>>I used to have 3 Cx states supported when I started with FreeBSD on 
>>version 5.3.  Since I upgraded to 5.4 and recently to 6.0, all I can see 
>>is just one supported Cx state.  I much wonder why. (?)
>What value do you have in /etc/rc.conf (if any) for
>performance_cx_lowest? It defaults to HIGH which will limit you to only
>the most power hungry sleep state (simple halt). This was made the
>default because some hardware was breaking when this was defaulted to
>LOW. T0 get other Cx states to be utilized, add
>'performance_cx_lowest="LOW"' to /etc/rc.conf.

i see.


# grep cx /etc/rc.conf.local


# sysctl hw.acpi.cpu
hw.acpi.cpu.cx_supported: C1/1
hw.acpi.cpu.cx_lowest: C1
hw.acpi.cpu.cx_usage: 100.00%

and, imho, cx_supported should list all available states, doesn't matter 
what is in rc.conf. (well, at least i reckon it's supposed to work that 


i already had 3 Cx states back on 5.3.
and when i had them, C2 was used most often (and C3 wasn't at all iirc).

so what has changed in the system please and how am i to get back my 
states please ??

many thanks,


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