CPU and GPU for transcoding

[AndreiP 4]

Hi, 

I'm a Emby Premiere user. 

I use a PC running on Windows 11 as a server for Emby. I would like to remove my RTX 3060 and to use it for another PC. The CPU is an Intel i7-9700.

I would like to know: 

1. How exactlly the Emby server will decide when to use my CPU or GPU to transcode the video? Is there any settings that I should do change in "Transcoding" tab? 

Please check my actually settings: 

https://i.postimg.cc/8zJZqVHS/1.png

2. If there is a lot of transcoding to do, will the server use the both (CPU and GPU) in the same time? 

Thank you. 

[GrimReaper 3308]

2 hours ago, AndreiP said:

1. How exactlly the Emby server will decide when to use my CPU or GPU to transcode the video? Is there any settings that I should do change in "Transcoding" tab? 

Select "Advanced" in first dropdown, under Enable hardware accelleration, set desired order of preferred decoders/encoders. 

2 hours ago, AndreiP said:

2. If there is a lot of transcoding to do, will the server use the both (CPU and GPU) in the same time? 

I'd assume you refer to iGPU as CPU is never excluded from transcoding process, though grunt will be offloaded to GPU (either integrated or discreet) if set/enabled, in the order of preference. But there is no load-balancing, 

[AndreiP 4]

22 minutes ago, GrimReaper said:

Select "Advanced" in first dropdown, under Enable hardware accelleration, set desired order of preferred decoders/encoders. 

Thank you! 

 

22 minutes ago, GrimReaper said:

I'd assume you refer to iGPU as CPU is never excluded from transcoding process, though grunt will be offloaded to GPU (either integrated or discreet) if set/enabled, in the order of preference. But there is no load-balancing, 

Thank you. 
So, by default, all charge of transcoding will go on CPU. And in the case if server needs more power, the Graphic Card will transcode also?  

[GrimReaper 3308]

2 minutes ago, AndreiP said:

So, by default, all charge of transcoding will go on CPU. And in the case if server needs more power, the Graphic Card will transcode also?  

Erm, no? 

28 minutes ago, GrimReaper said:

there is no load-balancing

 

3 minutes ago, AndreiP said:

though grunt will be offloaded to GPU (either integrated or discreet) if set/enabled

You have QS-enabled CPU, though few years old it can still hold its weight, integrated  UHD630 ain't a powerhouse but can still deliver (I have an 8th gen NUC still serving me just fine). Transcoding in software (pure CPU transcode) is a fallback, generally used as last resort), if you have provisions for any kind of HWA you should use it. 

[AndreiP 4]

Sorry, what does it mean Erm? 

 

About the transcoding I try to calculate if the CPU will be enought to transcode somes streams simultaneously (let's say 5). I understand that it depends of many factors (bitrate, codec, etc.). That's why I would like to understand how the server act if it need to transcode. 

As far as I understand from your post, the CPU is always involved and if it's not enought, the GPU will do that also to "help" the CPU. 

 

 

[GrimReaper 3308]

Maybe I wrote it ambiguously (though it didn't seem like that to me, personally), but I'll try to rephrase it: GPU can be either discreet (like your RTX3060) or integrated (like UHD630 in your i7-9700). Enabling HWA (hardware accelleration), available with Emby Premiere subscription, you're utilizing one or the other. If, for any reason, transcoding fails while using that graphic adapter, it'd fall back to softwate transcode, meaning using only your CPU computation, without graphics cores - I assume you can imagine that being a very demanding process and is, in general avoided, hence HWA. For your 5-odd transcodes, I reckon your i7-9700 with QuickSync should more than suffice (though as you've said, there's number of factors involved, so depending on your specific scenario maybe it wouldn't), IMHO you can go ahead and transfer that RTX3060 to another PC. Just make sure you have QuickSync enabled and on top of your preferred hardware decoders in Transcoding settings. 

Edited November 24, 2023 by GrimReaper

[AndreiP 4]

Thank you for your reply. It's clear now. 

 

I thought that the transcode could have been done by both: the integrate (CPU, UHD630) and discrete ressources (Graphic Card, RTX3060, in my case) simultaneously: it was my understanding from the begining. When I wrote CPU I ment UHD630 and GPU - RTX3060. Sorry, I was not very clear.
And I thought also that I can increse the capacity of my transcoding by keeping both. So, it was wrong. 

 

So, if I keep the RTX 3060, the Emby will choose more powerfull device (RTX 3060, in my case) to do the transcode and will be able to do more transcoding because it will use RTX 3060 (discreet vs integrated). 
If no, it will transcode, obviously, by using the CPU (UHD630). 

Another advantage to keep RTX 3060, it's to have a plan B in the case if something will go wrong with RTX 3060, like you wrote.  

25 minutes ago, GrimReaper said:

If, for any reason, transcoding fails while using that graphic adapter, it'd fall back to softwate transcode, meaning using only your CPU computation, without graphics cores

However, like you wrote, for 5 transcodes, the integrate UHD630 (CPU) should be enough.

30 minutes ago, GrimReaper said:

I reckon your i7-9700 with QuickSync should more than suffice

Finally, if for one reason it not work, I should keep RTX3060 in order to provide more resources for transcoding. 

 

Please confirm me if If I understood correctly. 

[GrimReaper 3308]

Sounds about right. 

Though, do note that RTX3060, while being a powerful card, has an artifically imposed limit of 3 simultaneous transcodes, something Nvidia's been doing for quite some time on consumer-grade GPUs (so you'd opt for their more expensive professional cards). You can check here as to how to circumvent that. 

[AndreiP 4]

Thank you very much! Let me check.

If the limit it's to 3 transcodes, it doesn't worth to keep RTX. 

Edited November 24, 2023 by AndreiP

[GrimReaper 3308]

Just now, AndreiP said:

Thank you very much! Let me check.

If the limit it's to 3 teanscodes, it doesn't worth to keep RTX. 

It's 5-10 minutes job to bypass that, you would get somewhere between 20 and 40 simultaneous 1080p transcodes with it unlocked. 

[rbjtech 4283]

The decision really depends on

a) How many simultaneous transcodes you require and

b) What resolution those transcodes are

A UHD630 is easily capable of 5-6 x 1080p transcodes, but it will struggle with 2 or more 4k transcodes.    

imo - Using an RTX3060 just for transcoding is a huge waste if your transcoding needs  meet the criteria above, as you'll be using a fraction of the cards total features/capabilities - and of course, you'll be powering it all the time the PC is on - yes, it won't be pulling huge power for 3D (graphics) work, but it will still be consuming additional power.

Edited November 24, 2023 by rbjtech

[AndreiP 4]

GrimReaper, thank you very much for your support! 

rbjtech, yes sure.