Lightroom Classic 9.2 Memory Leak

  • 1
  • Problem
  • Updated 5 months ago
OSX 10.14.6
iMac Retina 5k, Late 2015
4GHz Intel Core i7

Since upgrading to the current version of Lightroom Classic, v9.2, I've noticed what I assume is a memory leak that is causing slowdowns in the program.

Even when not doing anything in Lightroom (when it's in the background, for instance) it's using up to 20GB of RAM. It's currently sitting at 16.24GB of RAM while I type this. The problem remains until I quit and restart LR. CPU usage is as expected.

I am noticing slow and laggy develop sliders and cropping.

I'm currently having to restart the program multiple times a day.
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Justin Elledge

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  • Slowed down

Posted 5 months ago

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Photo of Bill


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This is a new Lightroom "feature". Happening on Windows as well and I'm on a system with 64GB of RAM. Surprisingly to me, V9.2 was an improvement as it was horrid with V9.1. I could only edit in V9.1 for about 30-60 minutes before the slowdown became intolerable, now I can go a couple of hours. 
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Justin Elledge

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I never had the issue in v9.1. Lucky me, I guess. 

What a bummer.
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Anthony Blackett

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Not seeing this on my Windows 10 system. I only have 16GB of ram on a laptop.

Rebooted and launched Lr Classic 9.2 and left it idle. It's been sitting idle for 3.75 hours now and hasn't used up much more ram than when it started. Currently using 870MB, which is about what it was soon after launch. Still, I find 870MB an extraordinary amount of ram for an application to be using while doing what essentially amounts to nothing.

However, this doesn't mean that there is nothing wrong.

If I actually edit a raw file, then memory use jumps to 1.8GB! A bit more editing pushes it up to 2.43GB. I then open two images in HR Merge and memory use goes to 4.4GB. Doing the merge pushes it up to 5.76GB, and editing the resulting dng finally reaches 5.9GB.

Leaving Lr Classic idle again, memory use stays at 5.9GB, indicating that it isn't releasing any of the memory resources it has taken to do a bit of editing and an HDR merge.

If I continue working with Lr Classic, the memory use continues to climb. A three-image pano merge peaked at 9.5GB while merging and went back to 6.95GB once finished. More editing in develop and I'm up to 7.15GB. Another three-image pano merge followed by editing in Develop takes it to 8.64GB.

Obviously, memory management in Lr Classic is very poor or even nonexistent.

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Justin Elledge

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Very similar to what I'm experiencing. For me, any new peak in memory usage becomes permanent until restarting the program. It will not go back down at all once a new peak is hit.
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There is a difference between locked memory and in-use memory. 

Memory exists not just to meet minimum functionality but to enhance performance. Take an example, checked about 30GB of large files to ensure they weren't corrupt, just scanned thru them. When done, I copied them to another drive. The copy took under 2 seconds because the files were all still in memory. The memory wasn't locked. If I had loaded a program that needed the memory, it was available. 
Lightroom Classic does a fine job of memory management. Take it from someone who spent over 45 years conducting high performance hardware/software analysis and tuning. 

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Just ran a test on Windows 10 Pro. Several of the sliders cause a momentary increase which falls back down.  The GB is at the end of each step. 
GB (rounded up) 
2.6   started in Library
2.7   go to keyword 
2.8   switch to Develop 
3.0   make a couple adjustments 
3.0   tab to next image 
3.0   adjustments 
3.2   minor adjustments to 10 more images
3.5   tab to next image & crop 
3.7   adjust Luminance noise
3.5   back down after adjustment complete
3.5   same again, peaked at 3.8 
3.6   next image, reset history, Basic Auto button, +36 Texture
3.9   10 more images with minor edits
4.1   same 
4.1   1 more image
4.7   2 images, heavy brush out and cloned out a hot pixel 
4.9   update to process V5, +56 texture added to next image 
4.9   jump to Library, uncheck keyword, return to Develop 
5.4   scan across 10 images, no edit changes
5.7   same 
5.8   same (momentary peaks to 5.9) 
5.8   10 more with 1 adjustment to 2 images 
6.1   scan across 10 images, no edit changes 
6.1   6 more with texture adjustments to 3 
8.8   export 462 pix at 4K resolution, 100% quality
9.7   quit, optimize and backup catalog 

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Rikk Flohr, Official Rep

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If this is new behavior with the 9.2 update, then it is more likely due to a bad install than an issue with the software. We've not seen widespread reports of this memory leakage since the 9.2 update. 


Often times, unusual memory usage following a Lightroom update is seemingly cured by reverting to the previous version of the software. In these cases, it is more likely that the newer version of Lightroom had a problem during installation causing the bad behavior and that reverting just appears to clear the issue. Often times, simply performing a clean reinstall of the latest version of Lightroom will clear the issue similarly eliminating the need to revert.Before reverting to the previous version, try the Lightroom Clean Install Procedure with the current version:
  • Close Lightroom
  • Restart the computer
  • Use the Adobe Creative Cloud App to uninstall Lightroom Classic
  • Restart the computer
  • Install Lightroom Classic via the Creative Cloud App without launching any other programs.
  • Restart the computer
  • Launch Lightroom
  • Wait 5 minutes
If memory issues persist after this procedure and reset of your preference file, then it is likely an issue that needs troubleshooting further.

A Preference File will survive a Lightroom uninstall/reinstall. Sometimes weird behavior is corrected/cured by resetting the preferences.

Reset Procedure:

1. Close Lightroom.
2. Hold down [Alt/Opt]+[Shift] while restarting Lightroom.
3. Overwrite the Preferences when prompted by the dialog.
4. Close Lightroom.
5. Restart Lightroom.

Does the performance issue continue after resetting the preferences?