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Constant Kernel Panics in Lightroom and ACR Freeze Mac and Force Reboot

Forum|Forum|4 years ago
May 28, 2021
6 replies
3369 views

When using the Develop module in Lightroom or ACR, after about 10 seconds my 2019 iMac's fans spin up to full speed, I get 100% cpu usage and the entire system completely locks up and then restarts about a minute later. If I disable the GPU acceleration in Lightroom I can use Develop but it is painfully slow to use in this way. I have an extremely large LR catalog that was working perfectly up until a week ago and my workflow has ground to a halt.

Adobe_Lightroom_Classic_2021-05-28-092628_Andys-iMac.zip

Crash or freeze

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Correct answer andyh30519225

Just wanted to follow up on this in case it helps anyone else, particularly since I haven't seen this particular recommendation listed anywhere else.

After going through all of the official and unofficial troubleshooting suggestions, including deleting preference files, reseting the GPU prefs, making a new user account on the Mac, checking admin rights etc etc etc - the issue turned out to be a monitor issue. About a month ago I added a second external monitor to my iMac (one 27" either side of the main display) running off USB-C naturally, like the existing external monitor.

Basically Lightroom Classic (Develop module) and Adobe Camera RAW crash when I have two external displays running off USB-C on my Retina iMac. When I drop back to one display I get no kernel crashes and no freeze-ups. Since Lightroom doesn't support more than one external display this isn't a huge issue, since I can just pull the plug on the second display while working in Lightroom and plug it back in when I'm done.

No idea why LR and ACR meltdown when you have two external displays plugged into your iMac, but I guess it's not a very common setup and I doubt it would rank very far up the list of bug fixes Adobe software engineers have to fix up. Anyway - hope this helps someone down the line.

K

kgdizainslv

Known Participant

Yes i have the sam problem with lightroom, i'ts painful to work and long time 😞

imac pro2019, osx 11.5, vega 56, 32gb ram i9

kentdesign

Community Expert

On efinal follow up. I personally have an iMac Pro 2017 (27 inch) running Catalina 10.15.7 (with a

Radeon Pro Vega 56 8 GB graphics card.) I have two external monitors, both those are 24 inch.

One is connected directly to the iMac, the other is connected to a THunderbolt 3 dock from OWC.

I just ran a test with all monitors on and launched Lightroom 10.2.

After trying mirroring the displays, not mirroring, moving Lightroom from one to the other, with both iMessages and Safari running, no crashes, no glitches, no slow downs at all.

So it might still be your connections or, as DJ_Paige said, the possibilities of a hardware failure with your system...

kentdesign

Community Expert

Just so we know, What do you consider and "extremely large LR catalog?"

A

andyh30519225Author

Inspiring

Currently 245,237 photographs.

dj_paige

Legend

Large catalog files not known to cause crashes or slowness (exception: making backups will be slow)

A

andyh30519225AuthorCorrect answer

Inspiring

Just wanted to follow up on this in case it helps anyone else, particularly since I haven't seen this particular recommendation listed anywhere else.

After going through all of the official and unofficial troubleshooting suggestions, including deleting preference files, reseting the GPU prefs, making a new user account on the Mac, checking admin rights etc etc etc - the issue turned out to be a monitor issue. About a month ago I added a second external monitor to my iMac (one 27" either side of the main display) running off USB-C naturally, like the existing external monitor.

Basically Lightroom Classic (Develop module) and Adobe Camera RAW crash when I have two external displays running off USB-C on my Retina iMac. When I drop back to one display I get no kernel crashes and no freeze-ups. Since Lightroom doesn't support more than one external display this isn't a huge issue, since I can just pull the plug on the second display while working in Lightroom and plug it back in when I'm done.

No idea why LR and ACR meltdown when you have two external displays plugged into your iMac, but I guess it's not a very common setup and I doubt it would rank very far up the list of bug fixes Adobe software engineers have to fix up. Anyway - hope this helps someone down the line.

kentdesign

Community Expert

I personally do have a mac and run 3 displays - and using Lightroom does not cause crashes.

I am on Catalina and not BIg Sur - maybe there is an issue with the OS, 2 monitors - did you add that second monitor just before LR started crashing?

kentdesign

Community Expert

Also, here is the info on using second monitors with Lightroom:

You can open a window that displays a second view of the Library. This second window displays the photos that are selected in the Library module, and uses the Library module view options that are specified in the primary Lightroom Classic window for Grid and Loupe view. The second window can stay open regardless of which module you’re working in, so it’s easy to view and select different photos at any time. If you have a second monitor connected to the computer that runs Lightroom Classic, you can display the second window on that screen.

When working with multiple windows, Lightroom Classic applies commands and edits to the photo or photos that are selected in the main application window regardless of what is selected in the second window. To apply a command to one or more selected photos in the second window, right-click (Windows) or Control-click (Mac OS) the selected photos in Grid, Compare, or Survey view in the second window and choose a command.

https://helpx.adobe.com/lightroom-classic/help/displaying-library-second-monitor.html

dj_paige

Legend

When using the Develop module in Lightroom or ACR, after about 10 seconds my 2019 iMac's fans spin up to full speed, I get 100% cpu usage and the entire system completely locks up and then restarts about a minute later.

These symptoms (fans running followed by computer restarting itself) are a very clear indication of thermal problems, brought on most likely by some failure of the cooling system in your iMac.

I have an extremely large LR catalog that was working perfectly up until a week ago

Another clear indication of a hardware problem (almost definitely in the cooling system). Everything works fine until some point in time when there are no known changes to a computer; but hardware can fail at any time.