Multi instances of OBS on Mac Mini M4

[ChrisAnes]

Hello and nice to meet you all here :)
I am trying to setup a Mac Mini M4 (basic model 16Mb Ram) for multi streaming on Youtube. I made to open 9 instances of OBS and make it running with videos on Youtube but after some seconds the videos on Youtube gone to POOR and lost many frames.
But the Mac Mini works perfect and the GPU monitor was about 40% the CPU about 18% and all the 9 OBS was running smoothly .
But as i said the streaming on the Youtube were lag and POOR.
I stoped 1 OBS (from the 9) and after i stop and start again all the other 8 OBS (streaming) start to work again and the Connection on Youtube been EXCELEND but for only some moments ... So i stoped one more .Now only 7 Instances of the OBS running and streaming and after i stoped and start again the streaming on each OBS the streaming on all the 7 now goes smooth and EXCELEND on Youtube.
I believe that only 7 instances of OBS can a Mac Mini M4 can Run on the same time.
The video that i am streaming is 1920x1080 and the bitrate at 6800Mbps at 30fps and the encoder i used on settings is the Hardware HEVS (my original video is 1920x1080 H265)
I have made the same test with the Mac Mini M1 and we manage to make it work only with 5 instances of OBS.
On my PC with the Nvidia 3060 i have manage to work only 4 OBS.
Do you have any experience on multi streaming with OBS on Youtube ?
Do you know why can not run more than 7 instances when the GPU monitor is about 40% and the CPU 17%?
Has to do more on the Hardware Encoder on the Mac?
I am looking to find a meter for the hardware encoder something like the Task Manager on Windows to see the Graphs on the mac but i have not find anything so far ...
Any help it will be great
Thank you Guys

 

[AaronD]

I'm REALLY surprised the Mini didn't choke all by itself! That's a LOT for just one machine to do!

Anyway, if the computer itself is (somehow) keeping up, then it's probably your internet connection that's a problem. Just one outgoing stream is often a challenge for most consumer connections, and you have *NINE*!?!

 

[ChrisAnes]

I'm REALLY surprised the Mini didn't choke all by itself! That's a LOT for just one machine to do!

Anyway, if the computer itself is (somehow) keeping up, then it's probably your internet connection that's a problem. Just one outgoing stream is often a challenge for most consumer connections, and you have *NINE*!?!

Hello and thank you for your help ! Well no the internet connection is perfect! I have an optical connection with full 150Mbps uploading! I only use about 40Mbps and the line is empty ! Something with the encoding chip i believe!

 

[AaronD]

...full 150Mbps uploading! I only use about 40Mbps...

There's a difference between average (measured) speed, peak (advertised) speed, and consistency/stability (needed for streaming). A different connection/service that advertises a much lower peak, and measures slower too, but turns out to be far more consistent, can actually be better to stream on.

Something with the encoding chip i believe!

I looked at your numbers again, and one especially stood out this time:

On my PC with the Nvidia 3060 i have manage to work only 4 OBS.

Encoding video in hardware doesn't work like other tasks do. It's a dedicated chunk of silicon that does nothing else. So it doesn't factor into the load measurement, and it just does what it does. Use it or not.

Some GPU's can encode 1 video stream at a time, some 2, and some 4. I think I *might* have seen one that does 8, but it was pretty niche and I was looking for something else, and so I might be mistaken on that one.

So I'm not surprised to see you top out at a standard number, with what looks like plenty of GPU capacity to go. In fact, you *are* full in the part that matters, and the GPU load doesn't include that. The remaining encodes must be done in software, and that's a LOT of work for the CPU to do!

If you have a second GPU that plays nice with the first (often a tall order all by itself), then maybe you can add their number of encoding channels. 4 GPU + 4 GPU + 1 CPU = 9 that you need.

More straightforward would be to use multiple machines. Ideally 9 of them, with each one responsible for a single stream. Put them all on a 10-port or bigger Ethernet switch (9 machines + 1 home run), and there you go.

 

[ChrisAnes]

There's a difference between average (measured) speed, peak (advertised) speed, and consistency/stability (needed for streaming). A different connection/service that advertises a much lower peak, and measures slower too, but turns out to be far more consistent, can actually be better to stream on.


I looked at your numbers again, and one especially stood out this time:

Encoding video in hardware doesn't work like other tasks do. It's a dedicated chunk of silicon that does nothing else. So it doesn't factor into the load measurement, and it just does what it does. Use it or not.

Some GPU's can encode 1 video stream at a time, some 2, and some 4. I think I *might* have seen one that does 8, but it was pretty niche and I was looking for something else, and so I might be mistaken on that one.

So I'm not surprised to see you top out at a standard number, with what looks like plenty of GPU capacity to go. In fact, you *are* full in the part that matters, and the GPU load doesn't include that. The remaining encodes must be done in software, and that's a LOT of work for the CPU to do!

If you have a second GPU that plays nice with the first (often a tall order all by itself), then maybe you can add their number of encoding channels. 4 GPU + 4 GPU + 1 CPU = 9 that you need.

More straightforward would be to use multiple machines. Ideally 9 of them, with each one responsible for a single stream. Put them all on a 10-port or bigger Ethernet switch (9 machines + 1 home run), and there you go.

Thank you again for your replay.
Well so far my tests give me that .
On mac mini M4 i can open and stream 7 OBS with no problem.
My upload speed and bandwidth is more than enough, i use for 7 streams 6.8Mbps x 7 = 47.6Mbps. And my optical line is giving me easily 140Mbps.
on my PC with the 3060 i can only stream 3 OBS at the same Mbps.
So far i see that the MAc Mini is a really powerful streaming machine.
So my future plan is to buy many Mac mini (M1 this time because i can find them used about 300Euro and it can stream 5 OBS same time) and Stream until my line is dead .
Thank you so much for the answers ..you know there are no information about all that in the internet ...