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1 Message

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310 Points

Tue, Oct 31, 2017 8:53 AM

Lightroom Classic: High CPU usage makes it unusable during export

After latest Lightroom Classic CC I almost can't work in Lightroom during export as it's using around 90% off mu CPU. Maybe exporting itself is a bit faster but when exporting 2000 pics I'm unable to work for about half an hour as there are huge lags. In the end I would rather prefer slower export working in a background and still have ability to work with pics without such noticable slow down. It was much better balanced before updating to Classic CC.
My CPU: Intel Core i7-6700K (4 cores, od 4.00 GHz do 4.20 GHz, 8 MB cache)

Responses

10 Messages

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296 Points

a year ago

Turning off half the threads is kinda ridiculous - if you're on a 16-thread machine, you're cutting all that fantastic performance in half. Setting Low priority for the process is less negative impact.

442 Messages

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6.6K Points

a year ago

Surprisingly it doesn't cut performance in half! Exporting 65 nefs using 12 threads took 4 min 20 secs, while using 6 threads it took 3 mins 45 secs. Intel is now selling cpus with hyperthreading permanently disabled. It can cause more problems than it solves. And Intel has recently been advocating turning hyperthreading off to reduce vulnerability to security problems, and is moving away from hyperthreading in some of its latest processors.

But I love having all my 12 threads at 100% while exporting or rendering previews. No doubt adobe could have a checkbox for exports as they do for previews.That would make both of us happy.

Bob Frost

10 Messages

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296 Points

You may find you're running into bottlenecks elsewhere of course. For example, storage and available memory. Holding 12 consecutive images in memory and applying all the changes soon adds up. Thus, your CPUs aren't being fed as they should.

442 Messages

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6.6K Points

a year ago

If you want to set low priority for the export process, make your own shortcut to turn LR on with export at low priority as in the following 

https://www.eightforums.com/threads/cpu-priority-shortcut-for-a-program-create-in-windows.40287/

Bob Frost

54 Messages

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890 Points

a year ago

I want to keep working on other images or in other programs during export. Please give me the choice.

And CPU usage seems to change over time somehow. Its always over 90% but after a while the other programs run smoother again??? on PC.

442 Messages

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6K Points

A computer is always waiting on something, otherwise everything would happen instantly. It is waiting on CPU, I/O, network, memory, etc. So when the cpu busy drops from 90% to 30% it is because it is waiting for something else such as reading or writing to disk. 
 
For example, I moved my Lightroom library and catalog to my GoogleDrive folder to have a cloud backup. Then with every update (adjusting a slider, etc), Google locked the appropriate file until the file was uploaded. Otherwise the file could get corrupted. To fix, I put a SSD on the PCIe bus, moved everything except the Lightroom Cache to that disk (dedicated to Lightroom), the cache is on a separate SSD, and use a file/folder synchronization program to periodically sync Lightroom with GoogleDrive. I use Second Copy 9.0. 
 

5 Messages

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110 Points

7 months ago

Hello,

I have the same problem, my PC (a DELL XPS 15 7590 with 32 GB RAM and 2 TB SSD) gets unusable while doing exports. I don't know this behaviour from other applications, working with other software should be possible while Lightroom is doing exports in the background. Of course the computer will get slower, but not unusable. What about a mechanism to lower down the priority when switching to other applications automatically, when Lightroom is losing the focus? Or an option in Lightroom about the priority. I'm working at home at the moment, because of Corona, as a developer for my company. And so it would be possible to do exports with Lightroom while working remote on my office PC. But it's not possible because of this problem. Very very annoying. 

I'm using Lightroom since the first version. In my opinion this problem is new since a few months, maybe...

Best regards
Friedemann

Champion

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5.2K Messages

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93.2K Points

On most computers, LR is good at limiting its total CPU usage during exports to about 85%, but on some computers, particularly those with a larger number of cores, LR uses close to 100%.  

This performance bug has been around for several years, and it should definitely be fixed. But if you need to get work done while waiting for Adobe to fix it, on Windows you can easily limit LR to use, say, 12 of 16 virtual processors:
https://feedback.photoshop.com/photoshop_family/topics/classic-cc-uses-90-cpu-during-export?topic-re...

442 Messages

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6.6K Points

7 months ago

If you really don't want to try any of the other tips above, why not start your export just before you go to bed?

Bob Frost

17 Messages

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382 Points

Bob, some of us use this software professionally and don't want to resort to work arounds. This is a serious issue for heavy users and needs to be addressed by Adobe.

2 Messages

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70 Points

7 months ago

Some ideas - update your motherboard as it could optimize how your CPU cores are tackling each IPC (instructions per clock).

Also, try setting the priority level of Lightroom to a lower level.  

It's not a complete fix, but I notice I can still use my computer a bit more while exporting 100+ photos.

442 Messages

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6K Points

7 months ago

Export performance test on:
  • HP Z440 
  • Xeon 6-core, 3.6/4 GHz
  • 64GB RAM 
  • from SSD on a PCIe adapter on the PCIe Bus, Samsung EVO 2TB 
  • to SSD on a SATA SSD, Samsung EVO 1TB 
  • Quadro K1200 
  • 4K monitor
3 tests, exporting 100 raw images to jpeg at 100% quality, 4K resolution, sharpen for screen:
  1. 2 min 54.4 sec - edited images 
  2. 1 min 33.2 sec - unedited images 
  3. 2-3X slowdown for editing concurrent with exporting another 100 unedited images, depending on the task. Library affected more than Develop, occasional flash of the develop window. 
 BTW, it is not a bug when something doesn't work the way we would prefer. 
 

3 Messages

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226 Points

When you are working live tethered in an event and need to export almost live while still capturing and with the client breathing on your neck, wanting both his exports and selecting the live shots, this is unusable and the client laughs at Lightroom or how you have a slow laptop even though you have a 4000$ machine to try and minimize that issue. It is a bug for that use case.

Champion

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5.2K Messages

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93.2K Points

7 months ago

There have been a few statements by Adobe employees over the past several years that, after Export was changed in LR 6 / CC 2015 to use multiple cores more effectively, they intended that Export would not consume all of the available CPU, which would allow for interactive use.  I found one of those statements here:
https://feedback.photoshop.com/photoshop_family/topics/lr-cc-2015-2-and-up-cpu-usage-on-export-on-25...

Adobe categorizes a post here as a Problem ("bug" in the vernacular) if LR is not behaving as the developers intended.  It's categorized as an Idea ("feature request") if the current behavior was intended by the developers.

So when LR uses 100% CPU during export, making interactive use very difficult, that's a Problem.

82 Messages

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1.6K Points

John,  I would characterize this situation as an Issue for users.  I read through some of the comments in that statement you referenced above, and it's clear that people have strong feelings about this situation, but there is real disagreement about if/how to change the current export situation.

I think for most users, they won't care if the issue is called a Problem or Idea.  They just want to get their issue addressed.  That said, the way that software teams work, there might be separate resource allocations between Problems and Ideas.  That also said, Adobe needs to recognize that regardless of what this issue is, it should be a high priority to fix this issue in a way that satisfies most/all people. 

The solution is really not that difficult.  It's just a question of priorities.

Phil Burton

Champion

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5.2K Messages

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93.2K Points

Fully agree. 

17 Messages

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382 Points

It looks like there are two camps, one that wants Lightroom exports to be super fast and don't care about any slow down. The other camp wants to be able to use Lightroom while exporting and don't mind a slower export.

Seems to me Adobe needs to look at some sort of cpu utilization setting in preferences that can be adjusted by individual users.

442 Messages

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6K Points

Priorities are difficult to set in Unix (MacOS) and Windows (less so than Unix but still not easy) due to the architecture of the operating systems. It can be done but is likely to cause problems with other processes. 
 
Hence the solution normally implemented for a multi-threaded process like Export and Import is to provide a preference for the number of threads that can be utilized by the process. Not ideal, priorities would be a better solution but not until we get an OS with a new internal architecture. MS is working on one that we should see in a couple years. Apple is gradually moving off MacOS to iOS (and variants) for all their products. 
 
In the interim, it "should be" (no guarantees) relatively straightforward to deliver a Preference, MaxThreads=nn. Ideally it could be in the Export dialog so that it could be varied based on other tasks in process. 
 

82 Messages

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1.6K Points

Without overcomplicating the solution, a thread limitation should be based on the total number of available threads in the system.

442 Messages

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6K Points

A percentage would likely be useful for the most people though I would prefer an absolute number. As I'm not having a problem with Export making my system unusable, perhaps my vote shouldn't count. 
 
While I've not done a scientific study of those who are having problems, they seem to be isolated to Mac users on relatively lightweight systems: all MacBooks and iMacs are lightweight hardware regardless of the Pro label. Windows and Mac Pro users seem to be unaffected though I would expect the problem to be just as serious on a Windows laptop even though Windows is somewhat more efficient at multi-tasking. 

17 Messages

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382 Points

I'm experiencing severe slow down on a new i9 Windows machine

442 Messages

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6K Points

Laptop or multi-drive desktop? 

17 Messages

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382 Points

Desktop, 32gb ram and Lightroom catalog on dedicated ssd

442 Messages

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6K Points

1. recommend that you turn RAPID mode for this drive
2. do other operations just slow down a bit or does the machine become unusable? Slowdown to be expected as resources are being shared but should not become unusable. 

17 Messages

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382 Points

Thanks for the rapid mode tip. I have read an article showing that ssd's only give a very minimal performance boost when exporting in Lightroom, even when compared to slow platter drives. Would rapid mode really make much of a difference? Exporting seems to be primarily a cpu intensive task.

https://www.pugetsystems.com/labs/art...

In response to your second question, everything slows down and the cpu is at 100%

Champion

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5.2K Messages

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93.2K Points

"Exporting seems to be primarily a cpu intensive task."

Indeed. I just did a quickie timing and my Macbook Pro exports a large batch of raws to the internal SSD at a rate of about 1 per second, with each exported JPEG averaging 8 MB.   So that's 8 MB per second written to the disk, an order of magnitude less than spinning disks (even cheap ones) are capable of.

Champion

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5.2K Messages

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93.2K Points

7 months ago

"It looks like there are two camps, one that wants Lightroom exports to be super fast and don't care about any slow down."

...and Adobe has said it was their intention that LR support the second camp.  I don't recall any statements from Adobe saying they would add an option to LR to support the first (but then they rarely indicate ahead of time their intentions with respect to feature requests). 

1 Message

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60 Points

4 months ago

 I've been measuring and it seems that the problem is solved in the latest LR updates.

PC, con CPU: Intel Core i5 6600K a 350 Ghz, RAM: 32 GB, GPU Intel HD Grafic 530 y Windows 10 Pro

C: Samsung ssd 970 evo plus 500gb (operating system and programs)

D: Kingston HyperX Fury SSD 240gb  (develop Ligthroom).

E: Western digital blue wd5000aakx 500gb (My documents)

F: Western digital blue wd5000aakx 500gb (Retouching Photoshop)

G: Western digital Green wd10earx 1000gb (Finished photo)


It is true that the CPU is at or near 100% when exporting from the Lightroom.


But it automatically drops the % if I'm using other applications:


 Yesterday I measured the export of 1305 ORF (Olympus raw OM-D E-M1 ) to Tif (91 MB) and the time was 41 minutes, while I was stacking with the Zerene Stacker and cleaning with the touch-up brush in Photoshop, no problem.




442 Messages

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6K Points

4 months ago

Ran a test on my system just for grins. 
 
1304 EM1 raw files 
    tried 1305 but one file was corrupt and 
    didn't see the need to rerun for just 
    one file 
No concurrent tasks 
Xeon 6-core 36/40 GHZ 
 
==== TIFF test ==== 

Image Format: TIFF
Compression: None
Color Space: Adobe RGB 
Bit Depth: 16 bits/component 
Resize: unchecked 
Sharpen: unchecked 
Include: All Metadata 
Watermark: unchecked 
 
12 threads driven with about the same load per thread 
CPU 77-85% 
Memory 6.01-6.08 GB
Disk 108-127 MB/s 
GPU 0% 
 
Duration: 22:05 
Exported Size: 108 GB  
 
==== JPEG test ==== 

Image Format: JPEG 
Quality: 100%
Color Space: sRGB 
Resize to Fit: Dimensions 
Don't Enlarge: checked 
3840x2160 
240 pixels per inch 
Sharpen: Screen 
Amount: Standard 
Include: All Metadata 
Watermark: unchecked 
 
12 threads driven with about the same load per thread 
CPU 74-86% 
Memory 7.4 GB
Disk 16-26 MB/s 
GPU 0% 
 
Duration: 24:58 
Exported Size: 7.63 GB

17 Messages

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382 Points

4 months ago

Appreciate the testing guys, but I'm still experiencing the same slow downs. 

For example I just exported a few PSDs from RAW files and not only was Lightroom unusable, my music playing in a Chrome tab was cutting out.

Please look at this Adobe, I use Lightroom A LOT and it is not only painful but also makes me less productive.

Champion

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5.2K Messages

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93.2K Points

Absolutely agree that Adobe should fix this.  While waiting for a fix, if you're on Windows you might consider this workaround:
https://feedback.photoshop.com/photoshop_family/topics/classic-cc-uses-90-cpu-during-export?topic-re...

17 Messages

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382 Points

Hi John, I've tried your batch file with updated paths but nothing runs. I'm on a i7 machine, what would be the hexidecimal mask to use?

Champion

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5.2K Messages

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93.2K Points

Hmm, that .bat no longer works with LR for some obscure reason. I've updated the post to include an alternative that works on my Windows 10 / LR 9.3:
https://feedback.photoshop.com/photoshop_family/topics/classic-cc-uses-90-cpu-during-export?topic-reply-list%5Bsettings%5D%5Bfilter_by%5D=all&topic-reply-list%5Bsettings%5D%5Breply_id%5D=20440860#reply_20440860

Champion

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5.2K Messages

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93.2K Points

Also, you'll need to find out how many virtual processors your i7 has. Go to Task Manager, click on the Performance tab, and look at the bottom for "Virtual processors".  I suggest changing the .bat file to use 3/4 of the number of total virtual processors. So if you have 8 total processors, change the file to use 6 processors by replacing "7" with "63"; if you have 12 total processors, replace "7" with "511"; etc.

17 Messages

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382 Points

Thanks John, can confirm this is working for me. Computer is definitely more usable but as I expected it doesn't help with my main issue - Lightroom itself is still unusable during exports.

14 Messages

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268 Points

3 months ago

This reply was created from a merged topic originally titled Lr Classic. 9.3 CPU Hog during export - Mac.

Exporting and publishing from Lightroom Classic 9.3 on my iMac (27" 5k 2017, 64gb RAM, OSX 10.15.5) renders the machine unusable..   CPU%  has gone over 800% !!!  ter is t
he computer inisorkeytokesn.

Right, I'll try again.  When I'm exporting rom LR Classic 9.3, the CPU usage is going through the roof - so much that I can't even type - the keyboard doesn't recognise half of the keystrokes because the system is running so slowly..  it's awful.  It's been getting slow the last couple of versions..  I've just had to install CPU Setter to limit the process in order to be able to edit this post.  

It's averaging 500-600% CPU resources, but has peaked at over 800%...