LinuxQuestions.org
Help answer threads with 0 replies.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Distributions > Slackware
User Name
Password
Slackware This Forum is for the discussion of Slackware Linux.

Notices

Reply
 
Search this Thread
Old 02-15-2007, 01:57 AM   #1
apad
LQ Newbie
 
Registered: Feb 2007
Location: Georgia USA
Distribution: Slackware 12
Posts: 3

Rep: Reputation: 0
Missing megahertz in /proc/cpuinfo on AMD64 chips


Someone please help put my adled brain to rest regarding this issue.

Using slackware 11.0, a default 2.4.33.3 kernel install tells me that /proc/cpuinfo shows my Athlon 64 3200+ as 2010.335 MHz.

That same install on an Opteron 148 at 2.2GHZ shows /proc/cpuinfo at 1001.000 MHz.

What did I do wrong?

I know there is some ACPI funkogistics going on here, as an Ubuntu 6.10 install lists /proc/cpuinfo at 1GHz on each chip. But if I run an intensive enough session and make the CPU burst up to 100%, the same /proc/cpuinfo shows the 3200+/148 chips as 2GHz/2.2GHz respectively during the burst. They both throttle back down to 1GHz after the session is over.

This does not occur on a default Slackware 11.0 install utilizing the 2.4.33.3 kernel on the Opteron 148. The 3200+ is listed out of the box @ 2GHz. The 148 is listed @ 1GHz. When I burst the CPU, the 3200+ reports correctly @ 2GHz; the 148 reports @ 1GHz.

What am I missing here?
 
Old 02-15-2007, 05:11 AM   #2
cathectic
Member
 
Registered: Sep 2004
Location: UK, Europe
Distribution: Slackware64
Posts: 761

Rep: Reputation: 34
ACPI, and in particular, "Cool 'n' Quiet", AMD's equivalent to Intel's SpeedStep.

Basically, when the processor is not doing anything, under a 2.6 kernel with Cool'n'Quiet enabled, Linux (via ACPI) switches the processor to a lower frequency mode when it's not doing very much. When work is required, the processor switches back to the faster mode, and when finished, back down again, and so forth.

The 2.4 kernels ACPI support is not as well developed as that of the 2.6 series - so with the 2.4 kernels, the processor is left running at full speed instead.
 
Old 02-15-2007, 07:45 AM   #3
raska
Member
 
Registered: Aug 2004
Location: Aguascalientes, AGS. Mexico.
Distribution: Slackware 13.0 kernel 2.6.29.6
Posts: 816

Rep: Reputation: 30
Quote:
Originally Posted by apad
...Using slackware 11.0, a default 2.4.33.3 kernel install tells me that /proc/cpuinfo shows my Athlon 64 3200+ as 2010.335 MHz....
Your Athlon64 3200+ is already running at full speed, there is nothing wrong with your kernel there. For the Opteron, it's already answered.
 
Old 02-16-2007, 10:36 AM   #4
apad
LQ Newbie
 
Registered: Feb 2007
Location: Georgia USA
Distribution: Slackware 12
Posts: 3

Original Poster
Rep: Reputation: 0
Thanks for the replies. The Opteron is showing up correctly now. Not sure what happened, I just powered the box down and let it sit overnight. When I booted it the next morning /proc/cpuinfo listed it correctlyl at 2211.368.
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
It is possible to modify the /proc/cpuinfo ? fc3_fan Linux - Newbie 21 01-30-2013 02:43 PM
Proc/CpuInfo sipsipi Linux - Software 4 03-03-2006 11:42 AM
Missing CPU in /proc/cpuinfo xerophyte Linux - Hardware 0 03-03-2006 10:20 AM
/proc/cpuinfo oops! feta Linux - Hardware 2 11-08-2004 10:16 PM
/proc/cpuinfo embsupafly Linux - General 3 12-29-2003 06:54 AM


All times are GMT -5. The time now is 05:35 AM.

Main Menu
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
identi.ca: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration