4 Replies Latest reply: Sep 5, 2011 11:16 AM by john beardsworth RSS

    What does the Previews.lrdata do; and how to move it to a different location than the catalog?

    crsouser Community Member

      I have been working to try to optimize the my system recently exclusively for Lightroom and tried placing the program, catalog, image files, previews all on different disks, changing preview sizes, cache size, and playing with different combinations to achieve optimal performance; including adding a small but fast SSD to the mix to try to host the different files.

       

      Though the testing has seen improvement, the one thing that has plagued my testing is the Previews.lrdata file that seems to insist on residing in the same location (and consequently growing huge) as the catalog despite telling Lightroom in the preferences I want my previews to be located in a different location.

       

      This file is also huge (LR Cat w/187,000 images - 2.6g / Current Previews.LRdata 35 gigs) and though it may not contain the actual image (or maybe it does) the re-arrangement of all of Lightroom files in the quest for optimization..seems to be negated (or at least not optimal) by not being able to move this file and I really don't understand what it does. It seems to be both an I/O problem as well as space consumption problem.

       

      As I would think that the Cache directly gets a filename that looks like a pointer and the catalog itself could just point to that vs. having to maintain a huge cache file on top of the cache itself.

       

      The problem I am primarily trying to solve is a a slight pause in between loading of each preview as I scroll through my images, the delay is noticable and sometimes can be 1-2 seconds in Library Mode with a 2008 Mac Pro (4 Core Xeon, 18 gigs of RAM, all disks at least 3Gbs SATA II) so that is why I suspect it may be the Previews.lrdata file. Regardless though of my particular problem...

       

      Has anyone found a way to move this Previews.LRData to a different location?

      Does anyone know what it actually does and contains?

       

      Christopher