GPU Bootleneck transcoding LIVE video

Gaming and Visualization Technologies General Topics and Other SDKs Miscellaneous
#1

Hello people,

I’m using a NVIDIA P2000 and FFMPEG for transcoding .
I whant to reach 20 TV Channels (live) transcoded to 3 ABR profiles each (360p,480p,720p)
I PULL video from Digital TV HeadEnd (mpegts over UDP).
Actually i have 14 Channels working OK and when i try to start transcoding #15 some channels begins to broken his video quallity
I have doubts about what is considered “GPU Bottleneck”

I read some DOCS, like this: http://on-demand.gputechconf.com/gtc/2017/presentation/s7111-abhijit-patait-nvidia-video-technologies.pdf
, in page 35 (ANALYZING PERFORMANCE BOTTLENECKS) i understand that 90%, 99% is considered GPU Bottleneck

So, in my scenery i have 65% for Encoding and %70 for Decoding (measured with “nvidia-smi dmon”)

gpu pwr gtemp mtemp sm mem enc dec mclk pclk

Idx W C C % % % % MHz MHz

0    56    77     -    81    41    61    65  3499  1721
0    59    77     -    79    40    58    64  3499  1721
0    60    77     -    79    40    60    64  3499  1721
0    48    77     -    77    39    57    63  3499  1721
0    60    77     -    81    41    59    65  3499  1721
0    63    77     -    81    44    65    66  3499  1721
0    60    77     -    78    40    59    65  3499  1721
0    57    77     -    80    41    59    66  3499  1721
0    57    77     -    77    40    55    64  3499  1721
0    60    77     -    78    40    62    65  3499  1721
0    58    77     -    81    42    63    67  3499  1721
0    53    77     -    80    41    60    66  3499  1721
0    53    77     -    78    40    58    64  3499  1721
0    49    77     -    79    41    60    67  3499  1721
0    56    77     -    79    41    56    70  3499  1721
0    45    77     -    78    40    61    66  3499  1721

This is what i have in my transcoder box:

  • - GPU Nvidia P2000 - Main CPU Intel i7-8700 CPU @ 3.20GHz - O.S. Linux Ubuntu 18.04.1 LTS (bionic) - Kernel:
Linux 4.15.0-43-generic #46-Ubuntu SMP Thu Dec 6 14:45:28 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

  • FFMPEG downloaded and compiled from NVIDIA
    ffmpeg version N-93005-gd92f06eb66 Copyright © 2000-2019 the FFmpeg developers
    built with gcc 7 (Ubuntu 7.3.0-27ubuntu1~18.04)

  • Drivers downloaded and compiled from NVIDIA
    filename: /lib/modules/4.15.0-43-generic/updates/dkms/nvidia.ko
    alias: char-major-195-*
    version: 410.79
    supported: external
    license: NVIDIA
    srcversion: 1283EC37DF82D5A8A902589

    filename: /lib/modules/4.15.0-43-generic/updates/dkms/nvidia-drm.ko
    version: 410.79
    supported: external
    license: MIT
    srcversion: 68386DCC84A5B791B6EEC80

This is my FFMPEG command:

/nvidia/ffmpeg/ffmpeg -re -vsync 0 -hwaccel cuvid -c:v h264_cuvid -deint 2 -drop_second_field 1 -i rtmp://localhost:1935/wtl/fc8an-glhik-j2poa-133i3 \
-vf scale_npp=1280:720 -c:a aac -c:v h264_nvenc -profile:v baseline -preset fast -level 4.1 -b:v 2500k -g 118.000 -f flv rtmp://10.1.10.30:1935/wtl-hd-dvr/fc8an-glhik-j2poa-133i3_720p \
-vf scale_npp=854:480  -c:a aac -c:v h264_nvenc -profile:v baseline -preset fast -level 4.1 -b:v 1500k -g 118.000 -f flv rtmp://10.1.10.30:1935/wtl-hd-dvr/fc8an-glhik-j2poa-133i3_480p \
-vf scale_npp=640:360  -c:a aac -c:v h264_nvenc -profile:v baseline -preset fast -level 4.1 -b:v 750k  -g 118.000 -f flv rtmp://10.1.10.30:1935/wtl-hd-dvr/fc8an-glhik-j2poa-133i3_360p \
-nostats -loglevel 0&
  • - If i use preset "hp" the video quality suffers - If i dont deinterlace....the video quality suffers - If i use level 4.0.....the video quality suffers

I missed something???..must i agregate some filter for best GPU performance???

Thanks to all !!!