OrangePi PC shows only 3 cores

elcct

Hello,

As in the subject, htop only shows 3 cores. Usually after reboot it shows 4 cores correctly.



It was on Ubuntu using kernel from scriptbin_kernel.tar.gz


What could be causing the problem?


Thanks,
elcct

loboris

adn replied at 2015-11-3 23:43
Yes, it also dynamically downclocks/underclocks the CPU (lowers the maximum allowed frequency).As e ...

Which OS/kernel are you using?
This problem was solved long time ago. In my kernel the frequency switching works as expected and the cores never  turns off (not before CPU temp reaches 95 C).
CPU runs at 1.53GHZ, it switches to 1.2GHz at 75C and returnes back to 1.53 GHz as expected.

@3Point14 any UART speed will most certainly not overheat the CPU.

hhrhhr

It is likely to overheat. When I run stress tests without an external heat sink, sometimes gets 2 kernel ;)
UART port at this time have rained reports about reaching 70 degrees and constant plug/unplug some kernels.

elcct

hhrhhr replied at 2015-10-6 22:01
It is likely to overheat. When I run stress tests without an external heat sink, sometimes gets 2 ke ...

Ah, that's cool then

Thanks!

adn

hhrhhr replied at 2015-10-6 22:01
It is likely to overheat. When I run stress tests without an external heat sink, sometimes gets 2 ke ...

Yes, it also dynamically downclocks/underclocks the CPU (lowers the maximum allowed frequency).As elcct said it needs a restart/reboot to return back the forclosed core. (Wait, what? )
It even does not sets back the highest CPU frequency limit. (In my case, whatever I do, it stays at 1.2GHz)
Right after that occurs I'm beginning to cooling it down actively (whit heatsink and fan).
This is a serious problem, if the H3 SoC does this permanently until the next reboot.
Please show us a way to figure out:
How to return back the highest frequency and the disabled core(s) while it's working chilled under (almost) no load!
I think this should happen automatically (in the background).

3Point14

hhrhhr replied at 2015-10-6 22:01
It is likely to overheat. When I run stress tests without an external heat sink, sometimes gets 2 ke ...

Try lowering your UART speed. At least, that's what I'm going to try. 115,200 might be overworking the CPU.

adn

loboris replied at 2015-11-4 16:51
Which OS/kernel are you using?
This problem was solved long time ago. In my kernel the frequency sw ...

Hvala na odgovoru Boris! ("Thanks for your reply Boris!" in Croatian)
I'm using Kali 2.0 Distro (sana) / with kernel 3.4.39
I've downloaded them (OS, uImage, script.bin) from the GDrive link given in your post. Thanks man, you rock by the way!

I'll try to change or update the kernel as well.

shrikantetc

Hi
I am also facing same issue, only 3 cores are working under stress.
i tried running  java based project for 2 hours and 1 cpu core gets stops.
But when i am not running that project  all 4 cores are working.

I am using latest script.bin and uImage files for orangepi pc website

what causes issue...?
Is there a bug in kernel...?
Any fix is available for this issue...?


Thanks
shrikant

shrikantetc

Hi
I am also facing same issue, only 3 cores are working under stress.
i tried running  java based project for 2 hours and 1 cpu core gets stops.
But when i am not running that project  all 4 cores are working.

I am using latest script.bin and uImage files for orangepi pc website

what causes issue...?
Is there a bug in kernel...?
Any fix is available for this issue...?


Thanks
shrikant

shooreg

what causes issue...?

It is usually a cpugovernor process that shuts down cores one by one to prevent overheating. However, if the load persisits high, it does not (as it was in my case) plug the cores back in unless told so forcefully. But that is not a really good idea - it hanges after some time.

Is there a bug in kernel...?

not really in the kernel, and not really a bug - it is a standard mechanism in linux, but in some cases it goes wrong.

Any fix is available for this issue...?

there are several ways to play with it:
- install the heatsink to cool the CPU (some guys even do active cooling)
- lower the CPU speed
- modify the cpugoverner policy

In my case, installing а 40х40mm heatsink teared from a dead motherboard's south bridge eliminated the overheat problem.