I have just received my Vim Pro, I have tried to do some compilations with make -j4 and some strees -c 4 with the ubuntu desktop 3.14.29 booting from mmc and booting from ssd with the https://github.com/150balbes version)
During the cpu load when the temperature is going to over 69/70 degree I get always a kernel panic.
With Android the board works fine.
this is the message: ( gpufreq_get_requested_power is the reason related to the GPU ??)
What is the physical temperature (if the external control laser thermometer) on the surface of the processor ?
Good option of monitoring temperature using a thermal imager. Which can display all temperature zones on the processor (CPU GPU etc).
I think the physical temp which we can measure from the CPU surface is different from the thermal sensor(inside of the CPU). And basically, the surface temp is around 55-60 degree when playing videos, and the environment temp is around 25-30 degree
I have used the command: stress -c 4
the compilation if use only 1 core or 2 core is fine, also stress -c 2 works fine.
Using the armbianmonitor -m during these operations the clock was 1.51 ghz, when the temperature is going to 69/70 celsius there is always a kernel panic,
I dont know if these value are the real value for the temp.
The cpu is without heatsink but I think that at 69 celsius the kernel should not going in kernel panic, or there is something that generate the kernel panic because the temp is growing up too fast ?
I dont think that play a video is a good testing method for this, usually the decoding process in software can’t use all the cores at the same time.
A stress test like compile a kernel or big library with make -j4 or j8 can stress better the system (also the stress is fine).
If You have the opportunity, try to test the behavior of this image (when run from external media) in two ways. 1. When you run the system WITHOUT a file “dtb.img” in the root of the FAT partition to run the stress test. 2. Copy from “dtb” in root file “gxl_p212_2g.dtb” and rename it to “dtb.img”. To run this version and check the stress test.
I’m not exactly checked, this is only my assumption - the decline is due to the fact that upon reaching the first threshold, (70) , the system shall automatically begin reducing the frequency\the number of working cores to reduce the load and limit temperature rise. But because of an error in the code (mine or not proper kernel) - there is a drop.