pi2 cpu stuck at 600mhz

[ric96]

I have been putting some cpu intensive tasks at my pi 2 including compilation on tangram source code with -j4 this does make the cpu usage go up to a 100% but the cpu frequency seems to be stuck at 600mhz and not to 900.
The temps remain below 70c and i am using stock raspbian downloaded from raspberrypi.org, no modifications what so ever.

Using

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watch -n 1 cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq

And RaspiCheck app

[ric96]

Even
arm_freq_min=900
Didn't help !!!

[MarkHaysHarris777]

. . .
Using

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watch -n 1 cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq

hi, if you start four process LxTerminals and issue the same command for cpu0, cpu1, cpu2,cpu3 then you will probably notice at least one of them will be running at 900 Mhz. (sometimes they all drop back to 600)

This is what you want, by the way; if the processor cores all ran at full bore then the little switching supply wart would get warm...

[ric96]

nope, still at 600mhz

[MarkHaysHarris777]

nope, still at 600mhz

rats. So, if you pin all four cores with something (compile, PI comp, whatever) all cores still show 600...?

Is the arm_freq set to 600 in the config.txt? This might just be a timing issue (I have noticed that I have to catch my cores at just the right time... mostly they are 600). But, if I keep checking they will bump to 900 even with normal operation let alone pinning the cores.

If I pin all four cores they all bump to 900... have you tried a reboot?

[ric96]

nope, still at 600mhz

rats. So, if you pin all four cores with something (compile, PI comp, whatever) all cores still show 600...?

Is the arm_freq set to 600 in the config.txt? This might just be a timing issue (I have noticed that I have to catch my cores at just the right time... mostly they are 600). But, if I keep checking they will bump to 900 even with normal operation let alone pinning the cores.

If I pin all four cores they all bump to 900... have you tried a reboot?

Yeah, i did check all that...
BOINC has been running for almost half an hour now, no change.....

[MarkHaysHarris777]

Well, maybe someone will chime in with some 'why' help. Got to thinking, how are you powering your PI? I don't know, but maybe the CPU steps down if it senses voltage drop? ... I mean, if not enough current is available from the supply (batt, or switching?) then maybe the CPU bumps down permanently until the power comes back up... have you tried a 2A power adapter?

[ric96]

Well, maybe someone will chime in with some 'why' help. Got to thinking, how are you powering your PI? I don't know, but maybe the CPU steps down if it senses voltage drop? ... I mean, if not enough current is available from the supply (batt, or switching?) then maybe the CPU bumps down permanently until the power comes back up... have you tried a 2A power adapter?

Psu is not the case, 2.1A sony powerful enough for an external hdd.

[rpdom]

Can you check that you've got the cpufrequtils package installed? I just checked my Pi2 and I didn't have that installed and it said it was sitting at 600MHz all the time. I installed that package and it is now switching between 600 and 900 as needed.

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rpdom@raspi5 ~ $ dpkg -l cpufrequtils
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name           Version      Architecture Description
+++-==============-============-============-=================================
ii  cpufrequtils   008-1        armhf        utilities to deal with the cpufre

If it doesn't show "ii" at the start of the line then it isn't installed.

[ric96]

Can you check that you've got the cpufrequtils package installed? I just checked my Pi2 and I didn't have that installed and it said it was sitting at 600MHz all the time. I installed that package and it is now switching between 600 and 900 as needed.

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rpdom@raspi5 ~ $ dpkg -l cpufrequtils
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name           Version      Architecture Description
+++-==============-============-============-=================================
ii  cpufrequtils   008-1        armhf        utilities to deal with the cpufre

If it doesn't show "ii" at the start of the line then it isn't installed.

Thnkx so much, that solved it but why is the default cpu governor at power save??
Makes no sense ...

[MarkHaysHarris777]

Thnkx so much, that solved it but why is the default cpu governor at power save??
Makes no sense ...

I agree. Also, I don't have cpufrequtils installed either, but my system is not in power-save by default?

[ric96]

Thnkx so much, that solved it but why is the default cpu governor at power save??
Makes no sense ...

I agree. Also, I don't have cpufrequtils installed either, but my system is not in power-save by default?

did you download your raspbian before the 2015-05-05, if so then this might be an issue with the latest firmware...

[PhilE]

[ Copied from the spurious github thread ]

It's a Raspbian issue.

On a Pi 1, the default CPU frequencies are min=700, max=700. Therefore to make use of the ondemand or performance governor you have to overclock. If you use raspi-config to enable overclocking then it will also enable the raspi-config service (sudo service raspi-config start) which switches to the ondemand governor (unless Shift is held during boot).

On a Pi 2, the default frequencies are min=600, max=900, and it is possible to use ondemand without overclocking. So it makes sense to always start the raspi-config service on a Pi 2 (or to change the kernel default).

We're looking into the best way to resolve this.

[ric96]

[ Copied from the spurious github thread ]

It's a Raspbian issue.

On a Pi 1, the default CPU frequencies are min=700, max=700. Therefore to make use of the ondemand or performance governor you have to overclock. If you use raspi-config to enable overclocking then it will also enable the raspi-config service (sudo service raspi-config start) which switches to the ondemand governor (unless Shift is held during boot).

On a Pi 2, the default frequencies are min=600, max=900, and it is possible to use ondemand without overclocking. So it makes sense to always start the raspi-config service on a Pi 2 (or to change the kernel default).

We're looking into the best way to resolve this.

Using cpufrequtils for now, will be looking forward to fixes...
Thnx

[ric96]

Update:

A patch has been released to solve the issue

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sudo apt-get update
sudo apt-get upgrade
sudo reboot

[solar3000]

I have a pi2 that hasn't been updated since I first got it in March.

I did a:

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root@raspberrypi # ping -f -c 1000 10.0.2.5 ; echo "hello world" ; cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
PING 10.0.2.5 (10.0.2.5) 56(84) bytes of data.
 
--- 10.0.2.5 ping statistics ---
1000 packets transmitted, 1000 received, 0% packet loss, time 443ms
rtt min/avg/max/mdev = 0.151/0.291/0.482/0.033 ms, ipg/ewma 0.444/0.296 ms
hello world
900000

before: 600MHz
after: 900MHz

I also didn't instal any freq modules.

[ric96]

I have a pi2 that hasn't been updated since I first got it in March.

I did a:

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root@raspberrypi # ping -f -c 1000 10.0.2.5 ; echo "hello world" ; cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
PING 10.0.2.5 (10.0.2.5) 56(84) bytes of data.
 
--- 10.0.2.5 ping statistics ---
1000 packets transmitted, 1000 received, 0% packet loss, time 443ms
rtt min/avg/max/mdev = 0.151/0.291/0.482/0.033 ms, ipg/ewma 0.444/0.296 ms
hello world
900000

before: 600MHz
after: 900MHz

I also didn't instal any freq modules.

Could be a recent issue with raspi-config because thats what gets updated an solves the problem

[ShiftPlusOne]

For the curious:
https://github.com/RPi-Distro/raspi-con ... its/master