* Athlon Mobile XP CPU speed problem
@ 2004-04-09 17:23 Andre Eisenbach
2004-05-06 10:05 ` Pavel Machek
2004-05-11 18:54 ` Andre Eisenbach
0 siblings, 2 replies; 4+ messages in thread
From: Andre Eisenbach @ 2004-04-09 17:23 UTC (permalink / raw)
To: linux-kernel
Dear Linux-Kernel developers,
My notebook [1], powered by a AMD Athlon XP2400+ (k7) is slowing down when
running on battery. This happens regardless of whether or not cpu frequency
scaling is enabled or not. /proc/cpuinfo still shows maximum frequency, but
the computer is definitely slowed down considerably.
ACPI cpu info shows "throttling contro: no" and "limit interface: no".
It seems like the slowdown occurs out of control of linux cpu frequency
scaling or ACPI.
What may cause this slow-down?
Is there any driver/kernel option which may let me control this behaviour?
Current kernel version used 2.6.5-mm1 with cpufreq and ACPI compiled in.
Thanks,
André Eisenbach
------
[1] Compaq Presario 2100z
/proc/cpuinfo:
processor : 0
vendor_id : AuthenticAMD
cpu family : 6
model : 10
model name : mobile AMD Athlon(tm) XP2400+
stepping : 0
cpu MHz : 1788.568
cache size : 512 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat
pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow
bogomips : 3538.94
/proc/acpi/processor/CPU0/info
processor id: 0
acpi id: 0
bus mastering control: yes
power management: yes
throttling control: no
limit interface: no
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: Athlon Mobile XP CPU speed problem
2004-04-09 17:23 Athlon Mobile XP CPU speed problem Andre Eisenbach
@ 2004-05-06 10:05 ` Pavel Machek
2004-05-10 3:26 ` Erik Meitner
2004-05-11 18:54 ` Andre Eisenbach
1 sibling, 1 reply; 4+ messages in thread
From: Pavel Machek @ 2004-05-06 10:05 UTC (permalink / raw)
To: Andre Eisenbach; +Cc: linux-kernel
Hi!
> My notebook [1], powered by a AMD Athlon XP2400+ (k7) is slowing down when
> running on battery. This happens regardless of whether or not cpu frequency
> scaling is enabled or not. /proc/cpuinfo still shows maximum frequency, but
> the computer is definitely slowed down considerably.
That may well be bios feature. Maybe battery is not even able to get
you enough juice for full speed....
Pavel
--
When do you have heart between your knees?
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Athlon Mobile XP CPU speed problem
2004-05-06 10:05 ` Pavel Machek
@ 2004-05-10 3:26 ` Erik Meitner
0 siblings, 0 replies; 4+ messages in thread
From: Erik Meitner @ 2004-05-10 3:26 UTC (permalink / raw)
To: linux-kernel
Pavel Machek wrote:
> Hi!
>
>
>>My notebook [1], powered by a AMD Athlon XP2400+ (k7) is slowing down when
>>running on battery. This happens regardless of whether or not cpu frequency
>>scaling is enabled or not. /proc/cpuinfo still shows maximum frequency, but
>>the computer is definitely slowed down considerably.
>
>
> That may well be bios feature. Maybe battery is not even able to get
> you enough juice for full speed....
> Pavel
I have also noticed the same problem. I have an HP nx9005(model DK993A
with an AMD XP-M 2400+) installed with Debian/testing and kernel 2.6.4
and 2.6.5. ACPI is used for power management.
When powered by AC the system performance is excellent. When powered by
battery, the system is so sluggish that I prefer to just not use it. It
is like it was running at 200 MHz.
This occurs with frequency scaling turned OFF and the CPU running at
1788MHz.
ONLY when I reboot with acpi=off does this behavior not occur - of
course all other power management is off too.
Note the differences in the results of the bogomips benchmark below. Let
me know if any other information is needed.
Thanks,
Erik
Relevant lines from kernel messages:
On AC power with ACPI:
============
============
nx9:~# bogomips
Calibrating delay loop.. ok - 1760.00 BogoMips
/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq:
1795500
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq:
532000
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies:
532000 665000 798000 931000 1330000 1795500:
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors:
powersave userspace performance
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_driver:
powernow-k7
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor:
performance
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq:
1795500
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq:
532000
/proc/cpuinfo:
processor : 0
vendor_id : AuthenticAMD
cpu family : 6
model : 10
model name : mobile AMD Athlon(tm) XP2400+
stepping : 0
cpu MHz : 1788.828
cache size : 512 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca
cmov pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow
bogomips : 3538.94
nx9:/proc/acpi/processor/CPU0# more *
::::::::::::::
info
::::::::::::::
processor id: 0
acpi id: 0
bus mastering control: yes
power management: yes
throttling control: no
limit interface: no
::::::::::::::
limit
::::::::::::::
<not supported>
::::::::::::::
power
::::::::::::::
active state: C2
default state: C1
bus master activity: 00000000
states:
C1: promotion[C2] demotion[--] latency[000]
usage[00029760]
*C2: promotion[--] demotion[C1] latency[100]
usage[00418342]
C3: <not supported>
::::::::::::::
throttling
::::::::::::::
<not supported>
On battery power with ACPI:
================
================
nx9:~# bogomips
Calibrating delay loop.. ok - 612.00 BogoMips
/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq:
1795500
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq:
532000
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies:
532000 665000 798000 931000 1330000 1795500
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors:
powersave userspace performance
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_driver:
powernow-k7
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor:
performance
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq:
1795500
::::::::::::::
/sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq:
532000
cat /proc/cpuinfo:
processor : 0
vendor_id : AuthenticAMD
cpu family : 6
model : 10
model name : mobile AMD Athlon(tm) XP2400+
stepping : 0
cpu MHz : 1788.828
cache size : 512 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca
cmov pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow
bogomips : 3538.94
nx9:/proc/acpi/processor/CPU0# more *
::::::::::::::
info
::::::::::::::
processor id: 0
acpi id: 0
bus mastering control: yes
power management: yes
throttling control: no
limit interface: no
::::::::::::::
limit
::::::::::::::
<not supported>
::::::::::::::
power
::::::::::::::
active state: C2
default state: C1
bus master activity: 00000000
states:
C1: promotion[C2] demotion[--] latency[000]
usage[00028280]
*C2: promotion[--] demotion[C1] latency[100]
usage[00379537]
C3: <not supported>
::::::::::::::
throttling
::::::::::::::
<not supported>
On battery power without ACPI:
================
================
nx9:~# bogomips
Calibrating delay loop.. ok - 1760.00 BogoMips
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Athlon Mobile XP CPU speed problem
2004-04-09 17:23 Athlon Mobile XP CPU speed problem Andre Eisenbach
2004-05-06 10:05 ` Pavel Machek
@ 2004-05-11 18:54 ` Andre Eisenbach
1 sibling, 0 replies; 4+ messages in thread
From: Andre Eisenbach @ 2004-05-11 18:54 UTC (permalink / raw)
To: linux-kernel
Here some additional information I picked up on the HP support forums:
> However HP seems to be adding a further amount of throttling when under
> battery power using 'Stop Clock' techniques. When minimal levels of power
> management are applied the processor is only running 1/3 of the time
> reducing to 1/6 of the time when using more stringent power settings (eg Max
> Battery)
Does that help in any way fixing this problem?
Short of a BIOS update, is there a way to work around this?
Please also see this recent LKLM email for reference:
http://lkml.org/lkml/2004/5/9/100
Thanks,
André
^ permalink raw reply [flat|nested] 4+ messages in thread
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2004-04-09 17:23 Athlon Mobile XP CPU speed problem Andre Eisenbach
2004-05-06 10:05 ` Pavel Machek
2004-05-10 3:26 ` Erik Meitner
2004-05-11 18:54 ` Andre Eisenbach
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