It looks like my VOXL is over-heating and down-clocking.

I've stripped the config down to the following:

voxl-streamer only. voxl-camera-server is stopped.

voxl-streamer configured to use video-test at 3840x2160x30fps with a bit rate of 1Mbps (I also tried 5Mbps and 10Mbps; the problems mentioned below were the same.)

 "video-test": {                   
     "input": {                    
         "interface": "test",      
         "frame": {          
             "width": 3840,  
             "height": 2160,        
             "format": "uyvy" } },
     "output": {                  
         "stream": {              
             "rotation": 0,       
             "width": 3840,       
             "height": 2160,
             "rate": 30,    
             "bitrate": 1000000 } }

Observed results with one stream going:

The video stream is still choppy (and very blocky at 1Mbps, as expected), lots of dropped frames.
voxl-streamer is consumping about 75% total CPU. thermal-engine is about 5%, and the rest of "other" and about 12.5% idle.

CPU consumption is 100% on CPU2 and CPU3, and about 50% on CPU0 and CPU1.

Mem: 1182424K used, 2678896K free, 17100K shrd, 16348K buff, 215972K cached
CPU0: 45.9% usr 21.1% sys  0.0% nic 29.2% idle  0.0% io  2.5% irq  1.1% sirq
CPU1: 66.0% usr 12.8% sys  0.0% nic 19.2% idle  0.0% io  1.2% irq  0.5% sirq
CPU2: 99.4% usr  0.1% sys  0.0% nic  0.0% idle  0.0% io  0.0% irq  0.3% sirq
CPU3: 98.5% usr  0.5% sys  0.0% nic  0.1% idle  0.0% io  0.7% irq  0.0% sirq
Load average: 5.98 4.01 2.74 5/591 3516
  PID  PPID USER     STAT   VSZ %VSZ CPU %CPU COMMAND
 3491  3228 root     S     781m 20.6   0 76.8 voxl-streamer -c video-test
 1995     1 root     S <  2154m 56.8   0  5.6 /usr/bin/thermal-engine
 2378     2 root     SW       0  0.0   0  1.0 [msm_thermal:fre]
  188     2 root     SW       0  0.0   1  0.5 [kgsl_worker_thr]
  249     2 root     SW       0  0.0   2  0.4 [kworker/u8:6]
 2212     1 root     S    18872  0.4   0  0.3 /usr/bin/voxl-cpu-monitor

voxl-cpu-monitor is warning of overheating, and slow clock rates:

Name   Freq (MHz) Temp (C) Util (%)
-----------------------------------
cpu0        307.2     81.6    12.72
cpu1        307.2     81.6    15.26
cpu2       1248.0     92.5    58.04
cpu3       1248.0     93.8    58.04
Total                 93.8    36.01
10s avg                       35.95
-----------------------------------
GPU           0.0     74.6     0.00
GPU 10s avg                    0.00
-----------------------------------
memory temp:       77.1 C
memory used:  1156/3770 MB
-----------------------------------
Flags
CPU freq scaling mode: auto
GPU freq scaling mode: auto
CPU OVERHEAT WARNING
-----------------------------------

And this is AFTER putting a heat-sink on the CPU/RAM stack (An unused copper RPi sink I had laying about.)

Also note the GPU is at 0%. Is the hardware H.264 encoder in the GPU, or part of the CPU?

Your suggestion of lowering the resolution and working my way up doesn't make sense, if "4k should work fine." Unless the resolution at which it starts working reliably will give you some hint at what the problem is. Other than lowering the resolution, I don't know how to scale this back any more to get it to work correctly. Can anyone else see something I'm doing wrong?

It really looks like its trying to encode in software. Is there an OMX daemon I need to start, or library to install, or something to get it to use the hardware encoder?

Here's a FLIR I took to confirm which chip was getting hot, and where the heat sink was needed. I think it's interesting to see that the heat is obviously only half the chip, showing that only two of the four CPUs were being stressed.
FLIR of VOXL 2022-02-11.jpeg

ModalAI Forum

SmittyHalibut