Node overhead: big performance hit with empty nodes

Since I've started using a fixed node structure in my grading, I've noticed a big slowdown with TNR. It seems that a node graph has an unexpected amount of overhead in terms of playback speed.

For example, in HD, using the standard candle project, I get about 21 fps playback with 4 TNR nodes. This is fine, since i never really need more than 1 TNR node.

Standard candle 4 TNR version

Screen Shot 2019-09-05 at 4.57.05 PM.png (31.13 KiB) Viewed 1459 times

However, if I create a new version and put 15 completely empty nodes in it, then a single TNR node, I get about the same less-than-realtime playback(20fps).

15 empty nodes and one TNR

Screen Shot 2019-09-05 at 5.01.46 PM.png (52.14 KiB) Viewed 1459 times

This is unfortunate, because my standard fixed node structure is 16 nodes.

Fixed node structure

Screen Shot 2019-09-05 at 4.56.46 PM.png (73.71 KiB) Viewed 1459 times

Even if I *disable* all of those nodes except for my TNR node, my playback still drops below real-time with a single TNR node active. This despite the fact that a grade with the same TNR node but no other nodes, plays back at 45fps.

It seems like there must be some major inefficiency under the hood here.....

(Resolve 16.1b2, OS X 10.14.6, AMD Radeon VII, 22-core 2.7GHZ processor, 64GB RAM)

Since I've started using a fixed node structure in my grading, I've noticed a big slowdown with TNR. It seems that a node graph has an unexpected amount of overhead in terms of playback speed. ...It seems like there must be some major inefficiency under the hood here.....
(Resolve 16.1b2, OS X 10.14.6, AMD Radeon VII, 22-core 2.7GHZ processor, 64GB RAM)

So you're using a Hackintosh running an AMD 22-core processor with Beta software. How does your drive I/O rate on the BMD speed test? What specific type of source material (codec, resolution, and frame rate)?

I typically run anywhere from 12 to 30 nodes in a fixed node structure, and I'll throw in an SNR/TNR node if I need one. I do bypass the nodes I don't need, but I can usually run at speed on a Trashcan Mac with no problem provided it's a 24fps HD timeline. Anything more than that will be a bit of a struggle.

This is a fantastic post. I'm really interested in responses.

So you're using a Hackintosh running an AMD 22-core processor with Beta software. How does your drive I/O rate on the BMD speed test? What specific type of source material (codec, resolution, and frame rate)?

I typically run anywhere from 12 to 30 nodes in a fixed node structure, and I'll throw in an SNR/TNR node if I need one. I do bypass the nodes I don't need, but I can usually run at speed on a Trashcan Mac with no problem provided it's a 24fps HD timeline. Anything more than that will be a bit of a struggle.

Even with 1920x1080 ProRes 23.98 footage on an HD timeline, reading from an NVMe SSD (around 2.5Gbps r/w), I can't quite play at speed with a single TNR node (2, faster, medium) if it is preceded by 16 empty, disabled nodes. This despite the fact that I can play back the same clip with THREE enabled TNR nodes (as long as there are no other nodes in the graph) at speed. It makes no sense.

Good evening.

I currently have the same issue. I have a fixed node structure, even with almost all of my nodes disabled, just having the nodes on the tree drastically degrades performance.

I have better performance with a 6K image and 4 nodes than a 1080P image with 20 but only four enabled.

Reproducible with any footage type/codec that I have tried.

Windows 10, Resolve 18.1.2, Intel 8086K, Corsair Vengence 128GB, RTX 3090, Samsung NVMEs

Good evening.

I currently have the same issue. I have a fixed node structure, even with almost all of my nodes disabled, just having the nodes on the tree drastically degrades performance.

I have better performance with a 6K image and 4 nodes than a 1080P image with 20 but only four enabled.

Reproducible with any footage type/codec that I have tried.

Windows 10, Resolve 18.1.2, Intel 8086K, Corsair Vengence 128GB, RTX 3090, Samsung NVMEs

Does the same thing happen with generated videos (eg the Effects -> Generators -> Four Color Gradient)? (To make the clip visible in the Color Page, create a compound clip)

I tested a UHD BRAW 24 fps clip in a UHD 24 fps timeline. I added a total of 21 nodes.

On or Disabled seemed to make no difference. Playback was 24 fps green.

Studio 18.1.2 on Windows 10
i5-2500K
RTX 3060 12GB VRAM

Same here.
I always use a standardised node tree and empty nodes don't have any significant impact on speed.

Same as Uli and the others. I'm on a 2019 Mac Pro and routinely use somewhere between 20 and 25 nodes, and it's been fine in terms of speed. I upped it a couple of weeks ago to 36 nodes just as an experiment for an entire project, and while the sheer number of nodes slowed me down in terms of workflow (just in trying to find the right node #), it didn't affect playback performance at all.

It seems to be difficult to reproduce, independent of the OS.
Try to export that timeline and open it in a fresh project. Still the same?

It seems to be difficult to reproduce, independent of the OS.
Try to export that timeline and open it in a fresh project. Still the same?

My post was from 2019. It subsequently became a known issue and was fixed a few versions ago!

Would you be so kind as to change the Subject of the original post so it's got Fixed: (or some such) in it?

Yeah, but Misha revived it. I doubt it's the same issue.

It is hard to reproduce. It does not seem to happen on other machines. I am still trying to work out what is causing this.

And here's a 36-node tree as an illustration (not necessarily what I use -- today it's just 21):



I often warn students that the problem with using a large node tree is it's tough to do without the Advanced Panels, which allow you to select a node number and immediately jump to it. Can't do that on the Mini or Micro panel (or the Tangent panels). Even on the Advanced, I start getting pretty fumbly over 25 nodes. And there are routinely people who use 30-40-50 nodes.

As arelated note: Walter Volpatto has a terrific 90-minute discussion of Fixed Node Trees, and he says a lot of what needed to be said:

https://ravengrade.com/landing/fixed-no ... -volpatto/

(Note that Ravengrade is a paid tutorial site, but I think they have a lot to offer.)