[FFmpeg-user] Prevent Circular buffer overrun

[Mitja Pirih]

Hi,

I am starting to experience Circular buffer overrun errors. This errors are more frequent than before. The only change that I made was to add more ffmpeg instances (from 24 to 30/35). All instances are on a nvidia M2000 card. From man and other google sources I understood this error usually means slow network performance, but I suspect it is not the case here as I am using mumudvb locally to grab video from 3 dual channel tuners and deliver multicast data on lo interface to the card. The load on GPU is approx 25%. RAM on card is approx 55% used. I think I am hitting a bottleneck. Anyone experienced enough to point me to the right direction?


Thanks

+-----------------------------------------------------------------------------+
| NVIDIA-SMI 384.111                Driver Version: 384.111                   |
|-------------------------------+----------------------+----------------------+
| GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
|===============================+======================+======================|
|   0  Quadro M2000        Off  | 00000000:01:00.0 Off |                  N/A |
| 74%   75C    P0    39W /  75W |   2424MiB /  4038MiB |     25%      Default |
+-------------------------------+----------------------+----------------------+

top - 13:07:55 up 27 min,  1 user,  load average: 4.71, 4.43, 3.72
Tasks: 252 total,   1 running, 251 sleeping,   0 stopped,   0 zombie
%Cpu0  : 21.2 us,  5.0 sy,  0.0 ni, 73.5 id,  0.0 wa,  0.0 hi,  0.3 si,  0.0 st
%Cpu1  : 24.0 us,  2.7 sy,  0.0 ni, 72.9 id,  0.0 wa,  0.0 hi,  0.3 si,  0.0 st
%Cpu2  : 21.6 us,  4.3 sy,  0.0 ni, 73.4 id,  0.0 wa,  0.0 hi,  0.7 si,  0.0 st
%Cpu3  : 18.7 us,  4.1 sy,  0.0 ni, 75.5 id,  0.3 wa,  0.0 hi,  1.4 si,  0.0 st
%Cpu4  : 18.9 us,  3.0 sy,  0.0 ni, 77.4 id,  0.0 wa,  0.0 hi,  0.7 si,  0.0 st
%Cpu5  : 12.5 us, 11.5 sy,  0.0 ni, 75.0 id,  0.0 wa,  0.0 hi,  1.0 si,  0.0 st
%Cpu6  : 18.8 us,  3.0 sy,  0.0 ni, 76.5 id,  0.0 wa,  0.0 hi,  1.7 si,  0.0 st
%Cpu7  : 18.7 us,  3.7 sy,  0.0 ni, 76.6 id,  0.0 wa,  0.0 hi,  1.0 si,  0.0 st
KiB Mem :  7830636 total,  2448092 free,  4157680 used,  1224864 buff/cache
KiB Swap:  8253436 total,  8253436 free,        0 used.  2466980 avail Mem 


Average:        IFACE   rxpck/s   txpck/s    rxkB/s    txkB/s   rxcmp/s   txcmp/s  rxmcst/s   %ifutil
Average:           lo  14454.69  14454.69  20429.68  20429.68      0.00      0.00      0.00      0.00
Average:         eth0   1829.76     26.03   2397.29      9.03      0.00      0.00   1805.93      1.96


ffmpeg version N-87875-gf685bbc Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.5) 20160609
  configuration: --prefix=/home/mitja/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/home/mitja/ffmpeg_build/include --extra-ldflags=-L/home/mitja/ffmpeg_build/lib --extra-libs=-lpthread --bindir=/home/mitja/bin --enable-cuda --enable-cuvid --enable-libnpp --extra-cflags=-I/usr/local/cuda/include --extra-ldflags=-L/usr/local/cuda/lib64 --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libspeex --enable-nonfree --enable-nvenc
  libavutil      55. 79.100 / 55. 79.100
  libavcodec     57.108.100 / 57.108.100
  libavformat    57. 84.100 / 57. 84.100
  libavdevice    57. 11.100 / 57. 11.100
  libavfilter     6.108.100 /  6.108.100
  libswscale      4.  9.100 /  4.  9.100
  libswresample   2. 10.100 /  2. 10.100
  libpostproc    54.  8.100 / 54.  8.100
Hyper fast Audio and Video encoder