WebRTC Performance Comparison (P2P vs SFU)

1. Introduction

With the last posting, we finished implementing the 1:N video conferencing WebRTC of P2P(Mesh) and SFU methods. The last part of the implementation was always a performance test, so I did a simple performance test. Please understand that the independent space between the server and the client would have been good for the test, but it was impossible under the circumstances.

2. Performance Test

2-1. Devices

device	description
CPU	AMD Ryzen 5 3600 6-Core Processor 3.59GHz
RAM	32GB
GPU	NVIDIA GeForce RTX 2060 SUPER
OS	Windows 10 Pro

2-2. Settings

• All clients and servers ran on one device.
• The 1:N method described above is based on general video conferencing.

2-3. Client Side Performance(Chrome browser CPU usage)

• The CPU share was based on Chrome browser because all clients ran on one device.

the number of users	P2P/Mesh(Signaling Server)	SFU(Media Server)
2	4%	5%
3	10%	8%
4	22%	9.5%
5	34%	18%
6	47%	25%
7	64%	30%
8	80%	30%

2-4. Server Side Performance(CPU usage)

• Since server was implemented as node.js, the CPU share was based on the Node.js process.

the number of users	P2P/Mesh(Signaling Server)	SFU(Media Server)
2	0.1%	2%
3	0.1%	13%
4	0.1%	24%
5	0.1%	32%
6	0.1%	41%
7	0.1%	48%
8	0.1%	50%

3. Results

3-1. SFU Server(Media Server)

• Real-time performance in several videos has decreased dramatically since the number of clients reached six.
• When there were more than seven clients, some images were stopped for a few seconds.
• Server Side had a very high CPU share compared to Signaling Server.
• Client Side had a CPU share of about half compared to Signaling Server, which clearly showed a reduced load on the Client side.

3-2. Signaling Server (P2P/Mesh)

• As the client increased, delay and real-timeness decreased slightly in the images, but the images did not stop.
• Server Side's CPU share remained at 0.1% regardless of the increase in the client.
• Client Side's CPU share increased significantly as the client increased.

[GitHub]

• 1:N P2P WebRTC
• 1:N SFU WebRTC

[References]

• 1:N P2P WebRTC
• 1:N SFU WebRTC
• WebRTC implementation method(Mesh, SFU, MCU)