Lightroom Classic 8.1: Constant high CPU usage

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  • Updated 3 months ago
  • (Edited)
As soon as I try to do any in LR, the CPU spikes to 100-200-400-600% 

I've tried:

  1. enabling / disabling GPU, 
  2. tried creating new catalog, 
  3. tried creating a single image catalog, 
  4. uninstall + reinstalled, 
  5. checked the folder permissions, 
  6. increased cache size, 
  7. creating smart previews, 
  8. creating 1:1 previews, 
  9. regenerating all previews, 
  10. disabling XMP creation. 


Nothing helps.The CPU becomes stable as soon as I stop doing anything and spikes with the most basic actions. 

Examples of actions that cause CPU spike: going from the Lib module to the develop module, going from one photo to another in the Library module, zooming in / out, scrolling in the library module, any kind of edits in the develop module. 

The system is a 15" Retina MBP, i7, SSD, 16GB RAM, AMD Radeon R9 M370X GPU running High Sierra 10.13.6

I would appreciate any inputs that can help resolve this..
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LM

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Posted 10 months ago

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Carlos Cardona

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Please give your Mac the "once over"! Run the free Onyx (https://www.titanium-software.fr/en/o...), reboot. (In Onyx just run everything in the Automation tab). Run Disk Warrior if you can ($120), (https://www.alsoft.com), reboot. If you can’t do Disk Warrior, at least run First Aid from Disk Utility. Also just doing a "Safe Boot" can clear out caches (restart, hold down shift until you see "Safe Boot" on the screen, then reboot normally.

If that doesn’t work try launching Lightroom from your other (admin or test) account, with a new catalog, as a test. Does it run OK? If it does it may be a corrupted preference in your Username/Library folder. Check The Lightroom Queen site for instructions on how to reset your preferences (https://www.lightroomqueen.com).
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Victoria Bampton - Lightroom Queen, Champion

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Hi LM, well done for posting.

As Carlos suggested, let's start by testing a brand new catalog in a different user account, as that rules out lots of problems in one go.
(Edited)
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LM

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Hi Victoria,

Thank you for responding. I had my admin try the above step, with the same results. We tried it on a single-image catalog BTW. so the catalog size doesn't seem to matter. 
Also tried with and without GPU enabled, the CPU keeps spiking even if I merely change the temperature on the Basic panel.

No sync, no face lookup.

I'm working with 40MB CR2 files - I'm hoping that the file size is not a factor?
(Edited)
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dmeephd

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File size is not an issue.  I work with raw files in the75-85MB range from the Canon 5DSR and the Sony Alpha 7RII and 7RIII.

As John stated below, the 100-200-400-600% usage is indicative of Adobe FINALLY getting around to attempting to implement symmetrical multiprocessing (SMP) and take advantage of multiple cores.

The problem you are experiencing in Adobe's half-assed effort in that regard which has been an abject failure.  An inexcuseable failure as the computer engineering effort to implement SMP is only about 25 years old.

Maybe the Adobe developers are only teenagers...???
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John R. Ellis, Champion

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"As soon as I try to do any in LR, the CPU spikes to 100-200-400-600% ... The CPU becomes stable as soon as I stop doing anything and spikes with the most basic actions. Examples of actions that cause CPU spike: going from the Lib module to the develop module, going from one photo to another in the Library module, zooming in / out, scrolling in the library module, any kind of edits in the develop module."

This is normal, expected behavior. Over the years, the number one complaint about LR (after all the bugs) is that it is too slow. In the last year or two, Adobe has worked hard to make LR faster, and one way they've done that is to make more use of your computer's processors.  


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Victoria Bampton - Lightroom Queen, Champion

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As John says, some CPU usage is expected because you're asking it to do some work. 

Going from Library to Develop is having to load a photo and then apply the edits, which is very complex code, so it takes a lot of calculation.
Going from one photo to another in Library may be having to build a preview, if it doesn't already exist or it's out of date because you've done additional edits.
Zooming in/out may be having to build a full size preview, for the same reasons.
Edits in the Develop module are having to apply the edits to the image data on the fly, and because it's a retina screen, it's having to apply it to a lot of pixels.

The CPU becoming stable again when you're not doing anything sounds like everything's working as designed, but it's obviously a surprise to you, so perhaps it would help to understand what you expecting to see when you use Lightroom.
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LM

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Hi Victoria,

Thank you for the detailed clarification.
To set my expectation, Is it normal for the CPU to go to 400-500% when editing an image or switching between photos or modules?
Is there any config on which this doesn’t happen? Or is there any way to keep the CPU usage at manageable levels ?

Thanks
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dmeephd

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Typically, if you have a six-core CPU and you see applications using multiples of 100% it simply means that those applications are using more than one core.  This is normal and desired behavior.

As long as your system does not become sluggish or nonresponsive, there is no problem.  If the system does become sluggish, then it is usually a lack of RAM.

I saw the very same behavior you describe on my MacBook Pro with dual-cores and 16GB of RAM.  It would become sluggish.

Moving to a MacPro with six-cores and 128GB the sluggishness went away by CPU processor use would routinely run at 400-500% divided between Lightroom and other applications.

If your system performs, I suggest stop looking at the CPU usage.  It's become like watching a front-loading washing machine—no added value.
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LM

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dmeephd, John, Victoria, thanks for the valuable inputs.
It is a quad core laptop. 
My problem is that once the CPU goes to 400-500%, the kernel task starts taking over in an attempt to cool down the system. This stage is reached within a few minutes, and then its all downhill from there.

Any ideas on how to manage this? 
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dmeephd

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So your system is overheating?

First of all, the fans and intakes might be dirty—they do require cleaning from time to time, especially if you live in a dusty area or have pet dander around.  To clean the intakes and fans one has to either have Apple open the case or you buy the special torxbit screwdrivers and do it yourself.  (It's really quite simple and the screwdrivers are readily available from Amazon.com.)

Second, the laptop might be sitting on a surface which is not conducive to cooling or there is poor airflow.  Solution: raise the laoptopso it's not sitting completekly on the surface, or buy a cooling fan platform to place it on.  Also available from Amazon.

You would be surprised how quickly the performance drops when the kernal task detects high CPU temps—this is by design intent.  To save your CPU from death by overheating.

There are several apps on the Apple Store for monitoring your Mac.  I use In-Site which allows me to monitor dozens of temps in my MacPro, including those on my external drives.  When the temps start to go up as I get very busy with the machine, I oft times have to redirect a small table fan toward the base of the MacPro trashcan to increase air flow.

There really ins't a software solution to increasing operating temps caused by hard-working programs.  (There was a Mac app a few years ago which would throttle down a given program if it started to use too many compute cycles or core percentages, but that was only a band-aid solution.  You don't want to slow down the app, you want to keep things cool so it will continue to run.)

On the other hand, the better a program is designed to use SMP on multiple cores, the better the machine will perform without issues.  AutoDesk has this hands down great.  Adobe...not so much.
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John R. Ellis, Champion

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I have a similar system, a MBP 15” Retina mid-2015 (4 cores). The fans start running as soon as the CPU is used heavily after just a few seconds, and they’re usually running whenever I use LR. But I’ve never observed overheating. Definitely get the fan and vents cleaned out. It’s normal for a laptop’s fans to run whenever the CPU is used heavily, even more so when the GPU is also in use, since the GPU can use as much power as the CPU.

See https://support.apple.com/en-us/HT201640
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dmeephd

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Yep.  Absolutely correct.  The laptops have vitually no heat sinks on the CPU or GPU...they NEED the fan on 100%.   (Even my MacPro runs the fan 100% of the time.)

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Richard Settineri

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Having the same issue with my 5K iMac 4ghz i7 cpu w/24gig RAM & AMD Radeon R9 M295X 4 GB video processor.
LR running slow to the point of frustration when using the spot removing tool. I wasn't having this issue with LRCC. I switched to LR Classic after getting the warning about CC will not work with future OS or something like that.
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Rikk Flohr, Official Rep

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Can you post a screen capture of the Performance screen above and note how you had it set previously?

How many spot removals are you putting on an image?
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Richard Settineri

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Only change I made was what you suggested. (unchecked the "use graphics processor. I tested the spot removal with only three or four spots removed. Not large or dragged circle of areas.
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Rikk Flohr, Official Rep

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Let me ask the question a different way: In a typical image (where you previously would see slowness) how many spot heals would you do on average?
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Richard Settineri

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I'd estimate 5-10 spots. I try not to go crazy fixing things. 
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Carlos Cardona

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Let's cut to the chase: Lightroom (now Classic) has had terrible memory management issues for a while (memory leaks, etc.) Yeah, it's doing a lot, but so are other programs that don't bring your RAM down to 3% available (when I had 16GB RAM). The solution? I got a 64GB RAM iMac now, and rarely go below 50%, with other apps open. The 16 cores all go to 100% sometimes, of course, but at least it's using all of them! I'm looking at you Photoshop (or is that fixed now?)
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Carlos Cardona

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I will admit that it has actually gotten better lately! Thanks coders!
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LM

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So based on the above replies (thanks to all who responded!) there seem to be 3 main factors that decide how much CPU and RAM will be used:
1. quantity of data to process (MP of image)
2. number of steps to process (global and local edits)
3. resolution of output monitor

As 1 & 2 cannot be really controlled, would it be correct to say that LR would work better on a lower res monitor, vs a higher res monitor, all other factors being the same?

My problem even now is that I have to repeatedly restart the system, LR CPU usage triggers the kernel task and then that task doesn't let go easily. 

Got the system cleaned, I run nothing else, except LR, I did notice that forcing the GPU to be always ON causes the system to heat faster. 

I am running this on top of a 4 fan cooling pad, but cooling pads merely recirculate the air around the system, so I don't think that helps by much.

So.. should I not use local edits at all?

Any other ideas would be most welcome!

BTW, Photoshop works quite well. Even with many layers, the system doesn't heat up much. 


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Nairn Watt

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I keep reading, the CPU usage should be 100% and that it’s working as a intended. No it’s a knee jerk reaction to multithreading not being designed correctly.


Using Lightroom Classic CC. Not sure if version but updated it 2 weeks ago. Though the behaviour below has been the case for at least a year.


While I agree that Lightroom should try using as much resource as is practical. What they have really done is make a mess of it.


I run a Ryzen 1700 8c/16t and 2600 6c/12t pair of PCs. Both with 16GB 3,000MHz ram, NVME boot and catalogue drives. When I import any files, already copied to my storage drive. The 1:1 preview build renders my PCs unusable. This is a coding problem, not a hardware or setting issue.


I’ve tried both CPUs at stock & overclocked at 3.8Ghz on all cores also with GTX1080 GPU enabled and disabled. Also no thermal throttling as my cooling solution keeps the CPUs below 70degrees C


Lightroom should have the option to allow for a priority of core usage. At least allow for a core/thread to be left for general usage. Even if minimised, my whole PC is unresponsive, why is there no background run option? No software should peg all threads to 100% and not have scheduling right to enable general usage like email checking. Even mouse responsiveness drops off the table.

I’ll add I really don’t mind 100% CPU usage. It’s the locking of the PC that I don’t agree with. I’d accept faster processing if I leave it to work or slower performance if I decide to use the PC at the same time.
(Edited)
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Carlos Cardona

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Nairn: it’s the 16GB RAM that jumps out at me, it’s NOT enough for today’s Lightroom. As you can read in my previous post, going from 16 to 64GB RAM (MAC or Windows) makes ALL the difference!
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Nairn Watt

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Thanks. I’m willing to accept that more memory will help. In saying that I did have 32GB and it wasn’t much different, I temporarily split it out when doing the other build.

It does still raise the question of why Lightroom is so unable to relinquish power to other processes. Yes when that happens, Lightroom will slow down. The problem is the option doesn’t exist.
I’m not complaining about the speed Lightroom works at, though it does cobble itself during imports. It’s how Lightroom effectively disables the multitasking aspect of a PC during import.

I’m no pro, this is all a hobby for me. I’m sure anyone with deadlines would rather let imports and previews work in the background while they start doing some work. Especially if they have multiple memory cards or shoots to import/work on.

I’m sure if I was to tweak scheduling priority in the OS I could improve things. From my experience it shouldn’t have to be done. You should be able to try on the application or an in application control to help performance to your own needs. My use case isn’t exactly out of the ordinary. Especially when you consider the value proposition of CC Photo subs.