MacBook Pro M4 really struggling with Node render

Ok, ive not been using Resolve for long, so im going to assume this is user error, but I cant see where im going wrong.
Im on a M4 pro MBP with 24GB, using the final release of DR20. Mac Os15.5

I have a 3.5min long 4k canon clog3 clip, and I keep trying to use the noise reduction on my second node, after a CST. Ive turned on Node cache and it took about 20-30mins to render the NR. The blue line went across really slowly but it got there. Then I had smooth playback. I can adjust nodes further down the chain without any issues. I saved the project a few days ago and have just gone back to it. The best I can get is about 12fps playback at half resolution. Full resolution (1080p timeline) drops to 1-3fps. This is totally unusable. The thing I cant figure out is why. The node cache is on, and the cache manager is showing a big file, so it's still cached, only it's not. Render cache is switched to user, but nothing is getting rendered. The number on the Node is now red again, but it's not re rendering anything.

What am I missing? This isn't the first time ive had to waste yet more time letting this node re render (had to do it about 4 times on the first day, as it kept re rendering. Nothing has been touched in the first node, and no cuts or edits done to the single clip.

Where have you put your cache folder?

It's on an external SSD which never gets disconnected.

Noise Reduction is one of the most demanding effects in Resolve. The M4 Pro's GPU might be struggling with 4K footage + NR.

A couple of things to try:

- Go to Project Settings and check your Render Cache format. Make sure it's set to a high-quality codec like ProRes 422 HQ.

- Try clearing the cache manually (Playback > Delete Render Cache > All) and re-rendering the node.

Sometimes just toggling the NR node off and on again can force it to re-evaluate the cache. Hope that helps

Thanks but its more the fact that i have to keep re rendering that is making mew loose interest in DR.
I understand that NR will slow everything down, thats why im trying to use Node Cache, but if i keep re rendering it then whats the point. It adds 20-30mins to my workflow time. Im happy to do it once, but not so often. It’s not even showing red, so i know notihng has changed before it.

Id say 1 in every 3 times i open this Project i see that the Node has cached, but it’s stuttering. It’s still blue, there is no redline above the timeline. I could of course turn the node off for now, i thought Node caching was designed to stop needing to do this.

Version 20.0000049

Opening my project force closes it every time on launch.
I was using magic masking
Polygon tools
And compound clips trying to achieve desired fx in fusion page which. After hours and days of self teaching.

Now I can not open that project but I can open others.

I am using an iPad Pro 2024 M4 With Magic Keyboard and bought it specifically for DaVinci resolve, I was prompted with an upgrade option so I upgraded to 20.00000.49

Please help as I am missing deadlines and this is my current work flow which is being hindered by this issue.

Too late to get my money back unfortunately, , but I think I'll just give up on Resolve. Came back to the project today and I have an 11GB cache file but no smooth playback. According to Resolve nothing is cached and it wants to do it all over again. I could re cache the node, but it seems stupid that i have to do this almost every time I use Resolve.Thats 20-30mins gone every time I open Resolve. I only have one file on the Timeline, no cuts or edits etc, an di just want to get some NR on the whole thing. I thought this was professional software but this just seems like the coding is very poor.

Guess I'll give FCP a go and take it from there.

Dave, I totally get your frustration — noise reduction is one of the heaviest effects in Resolve, and node caching should be the solution, not the problem. Based on what you've shared, here are a few things that might help (or at least explain what's going on):

1. Check if your cache is really on the external SSD
Just saying “the cache is on the SSD” might not be enough. Resolve only saves cache there if you specifically set the cache path in:

• Project Settings > Master Settings > Working Folders > Cache files location

If not set manually, it defaults to:

Code: Select all

/Users/USERNAME/Movies/DaVinci Resolve/CacheClip/

That’s on your internal drive, not the SSD — even if media or project files are elsewhere. Please double-check this setting in the project that’s giving you issues.

2. Use a lighter cache codec
You mentioned long caching times and choppy playback even after caching. Try switching the cache format to a lighter codec like:

• ProRes 422 (NOT HQ)
• DNxHR SQ

Go to Project Settings > Master Settings > Render Cache Format. These formats are easier for Resolve and macOS to read from, especially off external SSDs.

3. Don’t use iCloud Drive for media or cache
If anything is saved inside iCloud Drive (e.g. on desktop or documents if iCloud sync is on), macOS may offload parts of the file to the cloud to save space. This causes:

• Files silently going “offline”
• Cache being invalidated
• Horrible performance

To be safe, always store cache and media folders outside of iCloud — ideally on a local SSD with iCloud disabled for those folders.

4. System tools or macOS background processes can interfere
Some tools can slow down or even invalidate cache files:

• Antivirus software (Norton, Bitdefender, etc.)
• Cloud sync apps (Dropbox, Google Drive)
• Time Machine if your SSD is not excluded
• Spotlight indexing
• SSD “cleaning” apps like CleanMyMac

If you're not sure, try testing with a clean macOS user account and no third-party tools running.

5. External SSD may still “pause” behind the scenes
Even if the SSD is never unplugged, macOS can put it into sleep/power-saving mode. That may cause Resolve to “think” the cache is unstable or corrupt and silently recache it.

Try moving the cache temporarily to your internal SSD (just for testing). If caching becomes consistent, your SSD or macOS's handling of it might be part of the problem.

6. General advice on caching workflow

• Enable “Node Cache” on the NR node
• Set “Render Cache” to User mode
• Right-click the clip > Render Cache Color Output
• Wait for the full blue line above the clip

If the node is blue but playback is still choppy, you’re likely hitting I/O or memory bottlenecks — not GPU or CPU limits.

7. Known issue?
DR 20 is still maturing, especially with new Apple Silicon (M4). You're not the only one seeing flaky cache behavior. If you can, post your logs and system details to help the devs reproduce this. Or try the same effect in a clean project — it might be a project-level bug.

Hope this helps! Let us know what you find when checking the cache path and system setup. Don’t give up on Resolve just yet — you’re super close to a solid workflow.

Dave,
Do everything that Robert said above and if that’s still giving you a challenge, here’s some more. One of my system is a Mac Mini M2 Pro with 16Gb RAM and 512Gb storage, so it’s fast less comparable to yours. But I am able to render cache and playback smoothly - however with a few adjustments to my workflow.

1. I don’t put my NR after a CST or in between them (an IDT and ODT). My NR is before the IDT, usually my 2nd node. It’s there but I do not turn it on until final render to reduce noise or when I am ready for final delivery. This helps a lot while I’m scrubbing or playing back in edit or color tab.

2. I too have an external drive because of the limited internal storage. I have a TB4 enclosure with an NVMe 1Tb just for cache and it is my first drive in the cache settings. In addition I have SpotLight turned off on this drive (this is very important).

3. I generate proxy on all the files. If I have to import them directly, I transcode camera log codec (like slog clog) to ProRes 444 or 422HQ. The silicon Mac has the ability to deal with ProRes much easier. I don’t do this for BRAW at all, or ARRI Log. I use an open source software called ShutterEncoder to do the transcode. But I really do generate proxy for all the files that goes on my timeline.

4. If you’re editing, you don’t really need a 4K timeline. I just do everything on a 2K timeline even if my ingest are from 4K and 6K clips. When you’re ready to deliver, that’s where you can ref back to the original clips.

So yes, there’s a bit of prep work but you’re not going to get the frustration of very slow renders. Turn on NR when you’re ready to work on noise reduction but that would be the near to last activity before you do your delivery on the Deliver page. I hope this helps.

If this is too much work, then I would suggest getting a faster machine… my 2017 iMac Pro is what I used for more heavy lifting but I had that for a while and it has dual GPU and lots of RAM and super fast storage/cache. Today, you might seek out a Studio M2 Max and above if you’re looking at the Apple ecosystem.

One last point, Robert’s number 5 is important and absolutely has happened before. If you’re doing this, get a tb4 hub and then make sure you are connected to a tb4 hub that has power on itself. Don’t use the ones from Belkin or similar cheap hubs. The two brands I have great success are the CalDigit and the BlackJet. They’re expensive but worth every penny.

CalDigit Element - https://www.amazon.com/CalDigit-Thunder ... 175&sr=8-3

CalDigit TS4 - https://www.amazon.com/CalDigit-TS4-Thu ... 175&sr=8-1

AFT BlackJet RX4 - https://blackjetusa.com/products/blackj ... ng-station

They all have their own power supply so if the Mac power sleeps, your external cache drive is not.

I’m happy with my CalDigit Element and BlackJet RX4 Raiden TB4.