Hi there,
Lightroom stores temporary processing information and image/video cache to improve the app's performance.
Which version of Lightroom are you using and what is your operating system?
By default, Lightroom keeps the preview cache file, [Catalog name] Previews.lrdata, in the same folder as the catalog file, [Catalog name].lrcat. If you move the catalog file or store it separately from the cache, then Lightroom has to regenerate the previews. So keep them together. This will allow you to allocate larger cache space for Lightroom.
Also, increasing the cache size would be a lot beneficial, so 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:
- Choose Lightroom > Preferences (Mac OS) or Edit > Preferences (Windows).
- Click the File Handling tab.
- 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: