Hello
I’m using NVidia Quadro P4000 and NVidia Quadro RTX 4000 to transcode live video streams using Wowza Streaming Engine + NVDEC/NVENC.
With RTX 4000 I can transcode simultaneously less live streams than with P4000, even with much lower GPU encoder utilization, because of maximum GPU Power reached.
I’ve got 4 cards inside 1 mainframe and they all behave quite the same:
$ nvidia-smi
Tue Mar 2 14:19:56 2021
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 440.95.01 Driver Version: 440.95.01 CUDA Version: 10.2 |
|-------------------------------+----------------------+----------------------+
| 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 RTX 4000 Off | 00000000:02:00.0 Off | N/A |
| 43% 68C P0 79W / 125W | 2496MiB / 7982MiB | 23% Default |
+-------------------------------+----------------------+----------------------+
| 1 Quadro RTX 4000 Off | 00000000:05:00.0 Off | N/A |
| 47% 72C P0 74W / 125W | 1473MiB / 7982MiB | 11% Default |
+-------------------------------+----------------------+----------------------+
| 2 Quadro RTX 4000 Off | 00000000:06:00.0 Off | N/A |
| 52% 75C P0 97W / 125W | 1653MiB / 7982MiB | 19% Default |
+-------------------------------+----------------------+----------------------+
| 3 Quadro RTX 4000 Off | 00000000:82:00.0 Off | N/A |
| 33% 62C P0 67W / 125W | 1330MiB / 7982MiB | 12% Default |
+-------------------------------+----------------------+----------------------+
+-----------------------------------------------------------------------------+
| Processes: GPU Memory |
| GPU PID Type Process name Usage |
|=============================================================================|
| 0 6752 C ...ocal/WowzaStreamingEngine/java/bin/java 1693MiB |
| 0 6872 C /usr/bin/ffmpeg 395MiB |
| 0 6877 C /usr/bin/ffmpeg 395MiB |
| 1 6752 C ...ocal/WowzaStreamingEngine/java/bin/java 1461MiB |
| 2 6752 C ...ocal/WowzaStreamingEngine/java/bin/java 1641MiB |
| 3 6752 C ...ocal/WowzaStreamingEngine/java/bin/java 1318MiB |
+-----------------------------------------------------------------------------+
As you can see in above graphs, GPU utilization is low but GPU power reaches above 100W and starting one more transcoding process results in error messages about Wowza transcoder being “Video behind filter state change. New state: SKIP1FRAME”, which means it cannot transcode input frames in realtime.
I’ve got another mainframe with 4 P4000 cards and I can start more transcoding processes, than with RTX 4000, having GPU power on sane level (~50W):
What causes so high GPU power indication on RTX 4000 and is it possible to lower that to start more transcoding processes?