Denoise takes several minutes to complete

Adobe denoise is unuseable for those of us with "older hardware". I refuse to spend hundreds or (alot) more dollars on a new system when Topaz does the same thing in a fraction of the time. 

I have a similar problem on my computer.  One picture estimates 10 seconds, but usually takes 15 to 20.  I can do a similar image next and it says 10 seconds, but takes 5 or more minutes.    I will continue to use Topaz.

Update:

• One of the other people with the 'slow processing' problem upgraded his graphics card from a 4G to 12G and reports that processing times are now at least, tolerable. Topaz deNoise is still 9x faster, but the 6-minute processing for LRC is now under a minute. I'm going to do the same upgrade and will report back. (Of course, we shouldn't have to spend hundreds of dollars on new hardware to make this new feature work - especially if the competition can do it faster on the same cards we have now.)
• Another user corrected me to say that LRC DOES allow batch processing of denoise files. It's a different process (not the "sync settings" that we're used to, but instead one selects the group of files, moves the slider as desired, then processes. Still 6+ minutes per file, but hopefully the new graphics card will make that tolerable.
• After processing another 20+ files in Topaz and LRC, I've concluded that LRC does a very good job and is comparable to Topaz. One apparent advantage that LRC has (over just the Topaz RAW model) is that you can make some adjustments before denoising, which you can't do with the Topaz RAW model (you CAN do it with the other models). Note, we always want to do denoise early in the workflow - certainly before texture, curves, dehaze, clarity or sharpening.
• The LRC DNG output files remain about 1/2 the size of the Topaz DNG output files my original 50Mb RAW file becomes 160Mb after processing in LRC and 291Mb with Topaz deNoise. That IS significant, although after giving to my clients and waiting some time, I'll probably want to save in a format that takes less space.

Six minutes?  I wish!  Just tried my first file, and what took 16 seconds with Topaz took ~35 minutes with Adobe.  Yeah, you can point to my weak GPU, but I think it's the software. While running, my CPU is 13%, memory is 75%, and GPU is 1% utilized.  Ugh.

I'd be happy if denoise took 6 minutes. My sony a99ii files take 20 minutes each, compared to just about 4 minutes for Photolab DeepPrime, and I'm not sure that the result is any better. My machine is:

Intel(R) Core(TM) i7-8700T CPU @ 2.40GH

64 bit windows 10

32G RAM

Intel UHD Graphics 630

The GPU is on 100% for that 20mins.

Software problem I reckon - hopefully Adobe will fix it.

Another factor that should not be forgotten is that whatever Adobe did, it is leading to FAR better quality than Denoise AI/Photo AI give. Far fewer weird artefacts, no hot pixels that get amplified, no weird grid artefacts, etc. I am frankly blown away by the quality of these denoise results and it is completely reviving old images that I thought were not really scalable to the sizes I like to print. I will happily give up a bit of speed for this. You do need a very beefy GPU or a recent Apple Silicon mac to really use this comfortably though.

I think the Ian Lyons post that Victoria linked to may hold part of the answer to this. Hardware acceleration specifically for machine learning/AI might be a missing link that helps explain why some computers can process AI features so much faster than others, and might help explain why older computers take much more time.

On my mid-range but recent laptop, I have so far never seen a Denoise time longer than a minute. I just did some tests and below is what I got. My hardware list is at the end…really nothing special from a CPU/GPU point of view, so I strongly suspect it’s the Neural Engine machine learning hardware acceleration that cuts the times. And that machines with older AI acceleration hardware, or none at all, will have to take longer. The Neural Engine is only in Apple Silicon Mac processors, which might help explain why owners of older Intel CPU based Macs are similarly reporting much longer AI Denoise times in the minutes. On the Windows side, I wonder if times are consistently faster using an NVIDIA GPU new enough to have their more recent AI acceleration hardware. (I notice that D Fosse above only took 33 seconds using an RTX 3060 with 12GB VRAM. That GPU model was released the same year as my laptop.)

In my tests, while the GPU is very busy, the CPU is very quiet during AI Denoise, with other background processes using more CPU than Lightroom Classic. This looks very similar to video editing, where newer computers render video very quickly because they have both a powerful GPU and hardware acceleration for popular video codecs. An older computer lacks both, forcing rendering to the CPU, which takes many times longer, and costs a lot more power and heat.

Of course, this only looks at performance within Adobe AI Denoise alone. It does not explain why AI Denoise might be slower than Topaz or others on the same images. I expect Adobe will optimize competitive performance further after this first release.

- - -

Test results

24 megapixels (Sony ARW raw)

ISO 3200

Default Develop state, no edits

AI Denoise set to 40
Estimated time: 40 seconds
Actual time: 36 seconds

16 Megapixels (Panasonic RW2 raw)

ISO 800
Many edits and masks
AI Denoise 25
Estimated time: 30 seconds
Actual time: 28 seconds

16 Megapixels (Panasonic RW2 raw)
ISO 800

Reset to default Develop settings
AI Denoise 25
Estimated time: 30 seconds
Actual time: 27 seconds

Equipment:

MacBook Pro M1 Pro laptop (1.5 years old), 8 CPU cores and 14 GPU cores (yes, it’s the base model), with 32GB unified memory.

(Unified memory means the GPU integrated with the Apple Silicon SoC can use any amount of unused system memory.)

Lightroom Classic uses about 5.5GB memory through most of AI Denoise processing, but that more than doubles to 12–13GB near the end of AI Denoise. That still may have left large amounts of system memory available to the graphics/AI acceleration hardware.

No special preparation: 6 days uptime, lots of apps open behind Lightroom Classic.

"Remarkably slow" is a reasonable result if you have a low-powered GPU. So reporting it to Adobe will just result in having Adobe point to your GPU. AI Denoise is an extremely computationally intensive process, more than any other process in LrC.

It's your GPU that determines how fast Denoise will be.

My 16MP images are running about 9 seconds on one machine and 3 minutes on an old one. What's your graphics card? That's the main difference in performance.