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Participating Frequently
May 18, 2022
Question

RAM & swap usage (100GB over 30 minutes of work)

  • May 18, 2022
  • 5 replies
  • 5415 views
Hi all,
I am running Lightroom Classic 11.3.1 on my 2021 16" MacBook Pro (M1 Pro, 16GB RAM, 1TB SSD), on macOS Monterey 12.3.1.
I am noticing an absurd amount of RAM & swap usage. Over the course of 30 minutes of work, kernel_task and Lightroom Classic itself has written about 100GB to the SSD. This doesn't seem normal. Memory pressure is green with spikes to orange with light work, and over time it grows to consistent orange (60-75% memory pressure)

I'm working on 300 Sony a7S III files with Super Resolution applied to them beforehand (a new catalog with pre-enhanced photos already), so ~43MP DNG files around 200MB each.

Is there a solution to this high RAM & swap use?
This topic has been closed for replies.

5 replies

DdeGannes
Community Expert
Community Expert
May 19, 2022

The Author stated in the initial post, "I'm working on 300 Sony a7S III files with Super Resolution applied to them beforehand (a new catalog with pre-enhanced photos already), so ~43MP DNG files around 200MB each."

Just thoughts out of the box, exactly what edits are being done, on individual images or batch of images?

Are you working with Auto-Sync activated?

 

Regards, Denis: iMac 27” mid-2015, macOS 11.7.10 Big Sur; 2TB SSD, 24 GB Ram, GPU 2 GB; LrC 12.5,; Lr 6.5, PS 24.7,; ACR 15.5,; (also Laptop Win 11, ver 24H2, LrC 15.0.1, PS 27.0; ) Camera Oly OM-D E-M1.
Ian Lyons
Community Expert
Community Expert
May 18, 2022

But there does appear to be a bug somewhere that causes macOS to think an app is consuming gargantuan amounts of RAM.

 

Yes, Conrad C has made a good point and one that should not be dismissed. By way of example,  I've seen screenshot examples comparing iStats menus indicating many GB of free memory along with even more GB of compressed memory, which in theory is also free for use when memory is under pressure. Yet, at the same time both Activity Monitor and Terminal Top are indicating that memory pressure has far exceeded all that can be used and is therefore using large amounts of swap.

 

Above examples are on systems with 64GB of unified memory. So, any suggestion that the OP is asking too much of too little needs to be placed in context. Sure, 32GB of memory is preferable but not an absolute minimum. If it is a mimium, then Adobe are guilty of misrepresenting the requirements of their applications, and I very much doubt they'd be so stupid.

Walt Thirion Photography
Known Participant
May 18, 2022

@Ian Lyons Leaving aside whether or not there is a bug that is causing excessive swap, I want to address your comment about "minimum requirements". I see a lot of confusion over this point.

 

"Minimum requirements" means the program will operate and work. From the OP's comments, LrC is working and the OP is able to process images. However, there is excessive swap activity. That is a consequence of only having the minimum requirements. When physical memory isn't available, programs use "virtual memory" which is swapped in and out as necessary. When processing high res images, LrC needs more memory. If physical memory is not available, it uses virtual memory. So the program works but the penalty is lower performance and more swapping.

 

Now, as I said in one of my replies, I have heard of swap issues with the M1/macOS that affect all programs, not just LrC but I thought they had been addressed in the latest update. Not being an active mac user, I don't follow those issues as closely as I follow PC/Windows issues so I am not positive that it has been addressed.

 

Most tech companies try to market their products to as broad of a user base as possible so minimum requirements are often just that, minimum requirements for the program to operate. They are not necessarily the 'recommended requirements'. The recommeded configuration is highly dependent on the type of work being performed. Making small adjustments to JPG files is very different from detailed processing of high-res RAW files. I can easily max out cpu and memory working on 102megapixel raw files especially when stitching together panoramas or building an HDR. Would it work with the minimum requirements and swapping to disk? Probably... but I wouldn't be happy with the performance or the amout of swapping.

 

Conrad_C
Community Expert
Community Expert
May 18, 2022

I believe Ian’s answer is more correct. Although 32GB is better, 16GB Unified Memory on an M1 should be enough to get work done in Lightroom Classic with Memory Pressure not staying orange, and 64GB should be unnecessary. (The official Lightroom Classic system requirements are 8GB minimum and 16GB recommended.)

 

But there does appear to be a bug somewhere that causes macOS to think an app is consuming gargantuan amounts of RAM. I’ve seen it occasionally with different apps, including Photoshop and Bridge, even though the applications are not handling anything that would consume that much memory. It is not yet clear whether there is a bug on the Adobe side or the macOS side, but as Ian said, Adobe is getting a lot of reports about it and hopefully they will figure out what is going on.

Walt Thirion Photography
Known Participant
May 18, 2022

Yes, I've seen similar posts about the M1/macOS writing too much to the SSD even outside of LrC but I thought they'd fixed that with the latest update. Not positive as I'm a Windows user.

However, the OP mentions he's processing super res photos and that is a whole different story than Adobe's 'minimum requirements'. I know because I shoot medium format digital (102megapixel) with 16-bit raw files and I can see the amount of memory necessary. Even assuming Apple's claims about the M1 being more memory efficient, it's hard to get around the requirements of extremely large image processing. This is a vastly different scenario than "normal photo" processing.

 

Participating Frequently
May 18, 2022

I agree about the different kind of demands that 16-bit medium format files impose. Although even with a more "normal" workflow, like 85% of the time I'm working on 3000-5000 image catalogs of wedding photos, from 24 to 46MP cameras. The same issues persist with massive swap usage.

Ian Lyons
Community Expert
Community Expert
May 18, 2022

You're correct, it's not normal, but is also proving difficult for LrC engineering to reproduce and thus fix. Unfortunatley, it gets worse in so far as there aren't any guaranteed pain free workarounds at present, although one that seems to help users reporting similar issues is to turn GPU acceleration Off in LrC Performance preferences. Doing so shouldn't hurt you too much since Adobe use the Apple Neural Engine (ANE) for Enhanced Raw and Super Resolution with the GPU primarily being used for rendering the display. The same applies to the Ai masks. Where you 'might' find a slow down are LrC features that make heavy use of the GPU for processing and working on images that have alrerady been processed in app such as DxO Pure Raw or Ai apps from On1, Topaz, etc. Even so, I encourage you try switching off the GPU and sharing your observations as same may help others in a similar situation.

 

 

Participating Frequently
May 18, 2022

Turning off GPU acceleration doesn't prove much help. Lightroom eats less system RAM (say from 12 GB to around 5-7 GB) but swap use is still excessive. 

Ian Lyons
Community Expert
Community Expert
May 18, 2022

How are you measuring memory use? Activity Monitor, Top or third party app

Walt Thirion Photography
Known Participant
May 18, 2022

16GB of system RAM is pretty light to work on super res files which is why you are seeing a lot of swapping to the SSD. 

To me, 32GB would be the absolute minimum, 64GB would be a lot better.

Participating Frequently
May 18, 2022

Super Resolution is not a frequent part of my workflow. My work usually involves weddings with  3000-5000 images per project / catalog (after culling rejects from 7000-15000!). Still, Lightroom eats up a lot of RAM and swap in that scenario. In comparison, Capture One usually consumes 7-12 GB of RAM with very little swap use.