Ways to Speed Up Lightroom

16 or even 32GB isn't an unusual amount of RAM to have in a computer these days. So I'm surprised to hear that LR uses a pathetic 1GB cache by default and stores it on an HDD!

Cache memory should use fast RAM, and only swap to slower permanent storage after that gets filled.

Thanks for this useful link, @bgelfand! I wondered why I'd never had any any performance problems with Lightroom but I see that (even before reading the article) I'd already bumped up the cache to 5GB on my SSD. I'll read through the article and check whether I need to adjust my settings. Still it's a great read for anyone who's experiencing a slow Lightroom performance.

LINK Dramatically Speed up Lightroom Performance

16 or even 32GB isn't an unusual amount of RAM to have in a computer these days. So I'm surprised to hear that LR uses a pathetic 1GB cache by default and stores it on an HDD!

 

Cache memory should use fast RAM, and only swap to slower permanent storage after that gets filled.

I think you misunderstand what the term cache means in Lightroom. It is not the same as cache in Photoshop where cache is a private virtual memory pool. In Lightroom cache refers to either Camera RAW cache or Video cache. In this case the article is referring to Camera RAW cache. To quote Martin Evening, "The Camera Raw cache is therefore used to store the unchanged, early-stage raw processing data that is used to generate the Develop module previews so this processing step can be skipped the next time you view that image." In otherewords, the cache is used only for Raw files (in my case NEF files) and only the second or subsequent times they are opened in the Develop module, and then is used create a preview from the RAW file. Since it is a persistent file across Lightroom sessions, it must be stored on non-volatile media - SSD or HDD.

Video cache is used when viewing or editing Video files in Lightroom.

Increase the Camera Raw cache size

Every time you view or edit raw images in the Develop module, Lightroom generates up-to-date, high-quality previews. It uses the original image data as its foundation, and then updates the preview for any processing or adjustments that have been applied. The process is a little faster if the original image data is in the Camera Raw cache. Lightroom checks the cache for the original image data and can skip early stage processing if the image data is cached.

By default, Lightroom sets the Camera Raw cache to 1 GB. If you increase the cache size, it can store more image data, which in turn speeds the generation of previews of those images. Some Lightroom users find that increasing the Camera Raw cache to 20 GB or more can dramatically speed performance in the Develop module. To increase the Camera Raw cache size, do the following:

1. Choose Lightroom > Preferences (Mac OS) or Edit > Preferences (Windows).
    
    
   
2. Click the File Handling tab.
    
    
   
3. In the Camera Raw Cache Settings area, experiment with a Maximum Size of 10.0 GB or more.
    
   

To further speed the cache, keep it on a fast hard disk. To specify the location of the Camera Raw cache, do the following:

1. Choose Lightroom > Preferences (Mac OS) or Edit > Preferences (Windows).
    
    
   
2. Click the File Handling tab.
    
    
   
3. In the Camera Raw Cache Settings area, click Choose and navigate to the location where you want to store the cache.
    
   

I think you misunderstand what the term cache means in Lightroom. It is not the same as cache in Photoshop where cache is a private virtual memory pool.

He most certainly did, or the massive differences in how LR/ACR and Photoshop operate with memory. In PS, the entire image has to be held in memory (3x5 times the file size actually) or it uses scratch disk. LR is a parametric editor with a tiny memory overhead in comparison.

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Optimize Lightroom performance