12 Replies Latest reply on Mar 11, 2017 2:00 PM by rwattersjr

    Lightroom CC 2015.5 - Memory Leak?

    Mike CG

      I've just re-installed my computer after doing some hardware upgrades (12GB -> 16GB, 500GB SSD, new video card) and now if Lightroom runs for about 30-40 minutes, Windows alerts me that my system is out of memory.


      I restarted Lightroom and opened the System info window and watched the Real and Virtual memory used by Lightroom values just start a slow climb while the program was not even in use.


      I've seen similar posts about Lr and a memory leak, but not quite the same circumstances.


      I'm including the full Sys Info screen then just a couple instances about a minute apart each on the two Memory counters below.  Any suggestions would be appreciated.  The Creative Cloud app states I have current version.



      Lightroom version: CC 2015.5 [ 1067055 ]

      License: Creative Cloud

      Operating system: Windows 7

      Version: 6.1

      Application architecture: x64

      System architecture: x64

      Logical processor count: 8

      Processor speed: 3.3 GHz

      Built-in memory: 16366.4 MB

      Real memory available to Lightroom: 16366.4 MB

      Real memory used by Lightroom: 1063.8 MB (6.4%)

      Virtual memory used by Lightroom: 1060.0 MB

      Memory cache size: 572.7 MB

      Maximum thread count used by Camera Raw: 8

      Camera Raw SIMD optimization: SSE2,AVX

      System DPI setting: 96 DPI

      Desktop composition enabled: Yes

      Displays: 1) 1920x1080, 2) 1920x1080, 3) 1920x1080, 4) 1920x1080

      Input types: Multitouch: No, Integrated touch: No, Integrated pen: No, External touch: No, External pen: No, Keyboard: No


      Graphics Processor Info: GeForce GTX 950/PCIe/SSE2


      Check OpenGL support: Passed

      Vendor: NVIDIA Corporation

      Version: 3.3.0 NVIDIA 364.72

      Renderer: GeForce GTX 950/PCIe/SSE2

      LanguageVersion: 3.30 NVIDIA via Cg compiler


      Application folder: C:\Program Files\Adobe\Adobe Lightroom

      Library Path: D:\Miscellaneous\Lightroom\Lightroom Catalog.lrcat

      Settings Folder: C:\Users\Administrator\AppData\Roaming\Adobe\Lightroom


      Installed Plugins:

      1) Canon Tether Plugin

      2) Facebook

      3) Flickr

      4) HDR Efex Pro 2

      5) Leica Tether Plugin

      6) Nikon Tether Plugin

      7) SmugMug


      Config.lua flags: None


      Adapter #1: Vendor : 10de

        Device : 1402

        Subsystem : 32081462

        Revision : a1

        Video Memory : 1969

      AudioDeviceIOBlockSize: 1024

      AudioDeviceName: Speakers (2- High Definition Audio Device)

      AudioDeviceNumberOfChannels: 2

      AudioDeviceSampleRate: 44100

      Build: LR5x102

      Direct2DEnabled: false

      GPUDevice: not available

      OGLEnabled: true




      Real memory used by Lightroom: 1063.8 MB (6.4%)

      Virtual memory used by Lightroom: 1060.0 MB


      Real memory used by Lightroom: 1615.9 MB (9.8%)

      Virtual memory used by Lightroom: 1731.9 MB


      Real memory used by Lightroom: 1737.3 MB (10.6%)

      Virtual memory used by Lightroom: 1882.7 MB


      Real memory used by Lightroom: 1999.6 MB (12.2%)

      Virtual memory used by Lightroom: 2204.4 MB






        • 1. Re: Lightroom CC 2015.5 - Memory Leak?
          Todd Shaner Adobe Community Professional & MVP

          I suggest rolling back to LR CC 2015.4 as outlined here:


          Lightroom roll back to prior update version


          Change step 3 at the above link to read:


          3) Download and install the 2015.5 / 6.5 release from


          Try again with LR CC 2015.4

          1 person found this helpful
          • 2. Re: Lightroom CC 2015.5 - Memory Leak?
            ssprengel Adobe Community Professional & MVP

            Are you disconnected from the internet by any chance but were signed in LR when the internet disconnected, so the licensing info is at least cached? 


            I’ve seen reports of repeated CC-reauthorization attempts in LR using up resources.  I’m not sure whether the process involved is LR or CC, though, so may not have anything to do with what you’re seeing.

            1 person found this helpful
            • 3. Re: Lightroom CC 2015.5 - Memory Leak?
              Mike CG Level 1

              Thanks for the link - I haven't been able to try that yet but will take a look.  Does that mean 2015.5 has a known bug?

              • 4. Re: Lightroom CC 2015.5 - Memory Leak?
                Mike CG Level 1

                I wasn't disconnected - as soon as I start Lr (while connected) and I can watch the memory usage climb and climb until finally Windows reports I have a problem.

                • 5. Re: Lightroom CC 2015.5 - Memory Leak?
                  Todd Shaner Adobe Community Professional & MVP

                  Mike CG wrote:


                  Thanks for the link - I haven't been able to try that yet but will take a look. Does that mean 2015.5 has a known bug?

                  The best way to find out is rollback to 2015.4 and see if that fixes the memory laek. Numerous bugs have been reported, which is why I'm still using LR CC 2015.4.

                  • 6. Re: Lightroom CC 2015.5 - Memory Leak?
                    alanterra Level 2

                    I have a repeatable memory leak (unfortunately with both versions 2016.5 and 2016.4), reported at LIghtroom CC Memory Leak (Mac/El Capitan) | Photoshop Family Customer Community . Any advice is welcome.

                    • 7. Re: Lightroom CC 2015.5 - Memory Leak?
                      zoladd Level 1

                      Hi alanterra,


                      I do not understand why you might want to force a rebuild of all your previews, as I understand that Lr will build them as required.  I can see it might save a bit of time in certain circumstances, but given that you seem to be having problems rebuilding previews it might be better to just let Lr do its own thing.


                      However, to see if there was a generic problem with Lr and preview rebuilds I tried two tests.  For info I have a late 2015 Retina 5k iMac with 4GHz i7, 8GB memory, 500GB SSD and NEC PA271W 256x1440 monitor for photo editing.  My Lr catalog (about 5GB) and previews (was 5.62GB) are on the SSD, and my photos are on an external 5TB rotating drive.


                      First I renamed my Lr previews folder and then opened Lr and went to my top level folder which holds all of my 148,461 photos.  I then scrolled around in the grid view, thereby causing Lr to make new previews.  That is, I did not force a preview rebuild, just let Lr do its own thing.  CPU load went way up over 600%, memory load moved up but only to around 6GB for Memory used and stayed green in Activity Monitor.  I gave up after the previews folder reached about 2.5GB.  It did not look like Lr was going to have any problems.


                      I then renamed my Lr previews again, opened Lr into my top level folder and used Library Previews Rebuild All photos.  It scanned for previews for 5 or 6 minutes with CPU at around 170% and memory at around 1.2GB (still in the green zone).  It then started rebuilding standard previews with CPU running around 375% to 450% (dropping to around 250 after 30minutes)  and total memory used typically less than 5GB (around what my iMac shows when I normally use LR and have Firefox open and still in green).  Lr memory was around 1.8 to 2.0GB.   I did not try to do anything else in Lr at the same time.  Total Memory used fluctuated as high as 5.21GB but typically stayed below 5GB.  The highest Compressed memory for my LR was less than 1GB.  I note from your other posting that yours was over 61GB!  I let this run for over 30 minutes but it did not look like anything was going to happen so I stopped. 


                      I did open this forum and start composing a reply and doing some Finder checkups while Lr was going.  This did not cause me any problems but I did notice that CPU varied quite a bit - sometimes staying around 200-300% for several minutes and at other times staying around 450-550%.  I don't know why.


                      I am wondering if the problem may be related to your disks rather than Lr itself, but I don't know.


                      If I was you, I would try the following:

                      1.  Just leave Lr to do its own preview rebuilding, or, if you really need to force it, 

                      2.  Close all other applications and then do a single selection of preview rebuilding (eg only std or only 1to1), or

                      3.  Just make smaller selections and do them one by one till all done.

                      • 8. Re: Lightroom CC 2015.5 - Memory Leak?
                        alanterra Level 2

                        Thanks for the effort, @zoladd. In response to your comments:


                        1. I want standard previews of my photos because I find the amount of time I wait to see photos when scrolling to be much less if I have the previews pre-built. I always pre-build 1:1 previews for any photos that I am currently working on for the same reason.


                        2. Closing other applications doesn't seem relevant—when one app (Lightroom) needs 64GB of RAM on a 32GB machine, it will bring the machine to a halt (or, in this case, the machine will halt Lightroom) regardless of the other apps.


                        3. It would be really tedious to do smaller selections. I just want my previews built, and doing them in selections of say 5% of my photos would take days.


                        That said, I started your suggestion of building just one kind of preview, and so far that is working. I have built about 50K standard previews in about 18 hours, and Lightroom's memory footprint has stayed under 4GB. When that finishes, I'll start in on the 1:1 previews.


                        Either the bug is in building 1:1 previews, or it is in doing Standard and 1:1 simultaneously. When I have more information, I'll report it on the other forum. (Adobe, bless its heart, maintains two forums—one for discussions and one for bugs and suggestions—which makes it nearly impossible for the less-dedicated to follow discussions). I'll follow up here too as I find out more.



                        • 9. Re: Lightroom CC 2015.5 - Memory Leak?
                          alanterra Level 2

                          Just to bring this up to date. The memory leak I am seeing is repeatable (on my computer), appears in both LR 2015.4 and LR 2015.5.1, and is independent of plugins. However, it only occurs when I generate regular previews and 1:1 previews at the same time. It appears that if I generate the previews sequentially, there is no problem.

                          • 10. Re: Lightroom CC 2015.5 - Memory Leak?
                            zoladd Level 1

                            Thanks for the update.  At least you can now get your work done.

                            • 11. Re: Lightroom CC 2015.5 - Memory Leak?
                              Mohit Goyal Adobe Employee (Admin)

                              Hi MikeCG,


                              Please update Lightroom to 6.9/2015.9 version which includes the fix for Lightroom: Erroneous warning message on Catalog Backup | Photoshop Family Customer Community


                              refer: Lightroom CC 2015.9 now available




                              • 12. Re: Lightroom CC 2015.5 - Memory Leak?

                                I updated to 2015.9 earlier today and I am experiencing progressive memory leaks with both Photoshop and Lightroom as I edit photos.