1 2 Previous Next 76 Replies Latest reply on Mar 31, 2012 1:24 AM by ashleykaryl

    Found a significant LR4 speedup - regenerate ACR cache

    jfriend0

      Like many others here, after I upgraded to LR4, my performance went completely to hell.  It would literally take 9-10 seconds just to advance to the next image in the Develop module.  Marking an image for deletion would take 15 seconds.  I'm running a Q6600 - quadcore processor at 2.4GHz with 4GB RAM on Vista 32-bit.  By today's standards, it's not a terrific speed demon, but no slouch either and it worked fine for several years with LR3.  I mostly process D300 RAW files.

       

      After reading a lot of posts here about crummy performance, I wasn't able to find any tips that might help so I started poking around in the preferences/settings.  One thing I discovered was that my ACR cache was perhaps getting starved a bit for size.  It was set to 50GB, but it was on a drive that might not have that much free space.  I reasoned that if the cache couldn't quite be large enough to hold my working directory of images, then it might be thrashing and pretty much never loading from the cache.

       

      So, I moved my ACR cache to a new drive with lots of free space, increased the cache size to 100GB and then proceeded to regenerate the cache for the directory of 500 images I was working on by making a 2 point change in sharpening on all images and then regenerating all previews.  It took awhile to make all new previews for all the images, but after doing so - WOW my old performance was back again, even running on the new 2012 process.  I could move from one image to the next in the develop module in under a second.

       

      So, I don't know if it was low disk space, some sort of general caching problem, a corrupted cache or what, but after making those ACR cache changes, my LR4 performance is back neaer where the LR3 performance was.

        • 1. Re: Found a significant LR4 speedup - regenerate ACR cache
          SeanMcCormack Adobe Community Professional

          Just check that the old preview cache isn't orphaned on the old drive and taking up space.

          • 2. Re: Found a significant LR4 speedup - regenerate ACR cache
            jfriend0 Level 1

            Seán McCormack wrote:

             

            Just check that the old preview cache isn't orphaned on the old drive and taking up space.

             

            I hit the Purge Cache button before changing the cache directory for that exact reason.

            1 person found this helpful
            • 3. Re: Found a significant LR4 speedup - regenerate ACR cache
              SeanMcCormack Adobe Community Professional

              I just found the 'Like' button. Good man/woman/person.

              • 4. Re: Found a significant LR4 speedup - regenerate ACR cache
                areohbee Level 6

                For future reference, generating 1:1 previews (e.g. via library menu selection) also generates develop cache entries.

                • 5. Re: Found a significant LR4 speedup - regenerate ACR cache
                  rosalynsam Level 1

                  I have significant problems with near lock up in LR4 and have posted a discussion (it takes HOURS to import a couple hundred photos, minutes to load a photo just to view sometimes).  There have been no suggestions in reply to my original post -so maybe I can tag along here for some assistance?  Please? In LR, I opened the preferences (in Edit) and found that my Camera Raw Cache Settings were set at 1. GB maximum size, with the Video Cache set at 3.0 GB.  Hate to be dense, but I want to be sure I am not causing with more problems.....so, I should purge cache on each first, then change maximum size to 100? Since mine is set on 1. that seems pretty drastic, since my system says it has 308 GB free out of 465. 

                   

                  I have an HP server which I can can use (instead of the default C drive which it is set to). My system is less than 2 years old,  Windows 7- my processor is AMD Phenon(tm)  II x 4 925 Processor.  My hard drive back up has plenty of space -  4 terabytes.  Could Purge Cache and change these settings in any way cause another problem?  Should I change this to my hard drive -if so, would I use the same file location, except change to my server? 

                   

                  I have a Mac with the same cache settings, and it is lightening fast with LR3 compared to this.  I really don't know how to ask the right questions -my knowlege about computer systems, etc. is limited.

                  • 6. Re: Found a significant LR4 speedup - regenerate ACR cache
                    SistersCountry Level 1

                    Rosalynsam,

                     

                    The 1 Gb seems very low. I just checked my cache folder and it is actively using around 3 Gb and has not done extensive work since a last purge a few days ago. 100 Gb may be more than you need but I think suggestions to allot at least 20 Gb are common. Mine is set for 35 Gb but is probably more than needed. I believe that the Video cache is just for displaying video files in LR and has no effect on still photos.

                     

                    I would not think putting your cache on a network server a good idea. Network connections are not fast compared to drive writes. You would want it on a fast local drive for best performance. If you have more than one drive you may want to see if separating the catalog and the photos helps out your performance at all.

                     

                    Another thing to try would be to totally delete your Previews and see if letting them rebuild from scratch helps out at all.

                    • 7. Re: Found a significant LR4 speedup - regenerate ACR cache
                      Keith_Reeder Level 5

                      SistersCountry wrote:

                       

                      Rosalynsam,

                       

                      The 1 Gb seems very low.

                       

                      50 gb here...

                      • 8. Re: Found a significant LR4 speedup - regenerate ACR cache
                        jfriend0 Level 1

                        rosalynsam wrote:

                         

                        I have significant problems with near lock up in LR4 and have posted a discussion (it takes HOURS to import a couple hundred photos, minutes to load a photo just to view sometimes).  There have been no suggestions in reply to my original post -so maybe I can tag along here for some assistance?  Please? In LR, I opened the preferences (in Edit) and found that my Camera Raw Cache Settings were set at 1. GB maximum size, with the Video Cache set at 3.0 GB.  Hate to be dense, but I want to be sure I am not causing with more problems.....so, I should purge cache on each first, then change maximum size to 100? Since mine is set on 1. that seems pretty drastic, since my system says it has 308 GB free out of 465. 

                         

                        I have an HP server which I can can use (instead of the default C drive which it is set to). My system is less than 2 years old,  Windows 7- my processor is AMD Phenon(tm)  II x 4 925 Processor.  My hard drive back up has plenty of space -  4 terabytes.  Could Purge Cache and change these settings in any way cause another problem?  Should I change this to my hard drive -if so, would I use the same file location, except change to my server? 

                         

                        I have a Mac with the same cache settings, and it is lightening fast with LR3 compared to this.  I really don't know how to ask the right questions -my knowlege about computer systems, etc. is limited.

                         

                        One of my symptoms before fixing my cache was that importing was ridiculously slow (hours to import a few hundred images) so my experience does overlap with your symptoms.   How big a cache you need depends upon what you're processing and how many you work on at a time.  I presume the ACR cache (which is what I wrote about here) is mostly (or perhaps only) used for RAW images so it's most applicable if you shoot RAW.  Secondly, you need to think about your working set of images (how many you work on at a time).  What you want is a cache that is big enough to hold cached versions of every image in the set you work on.  That way, you can import the images into LR which will build previews and fill the cache in the process and then you can go back and work on your images and they will all be precached.  If your cache size is a little smaller that the working set, then by the time it gets to the end of building previews, the cache is full and it's kicking your first images out of the cache.  Then, you go to start working on the first images and there's nothing cached so it keeps having to back to the RAW file for every new image.  This is when it's going to be really slow.  OTOH, if your cache is larger than your working set, then all images you are working on in a particular shoot can stay in the cache for the duration of working on them.

                         

                        I think the norm for the ACR cache is around 50GB just to make sure it's big enough for a large shoot.  1GB is miniscule and won't be doing you much good at all.

                        • 9. Re: Found a significant LR4 speedup - regenerate ACR cache
                          Scooby007 Level 3

                          Adobe recommends ACR cache of "10gb or more" for Lightroom

                           

                          http://helpx.adobe.com/lightroom/kb/optimize-performance-lightroom.html

                           

                          I think the norm for the ACR cache is around 50GB just to make sure it's big enough for a large shoot.

                           

                          That would be one heck of a shoot - about 140,000 images! (with the cache per image for a 21mp capture averaging 350k)

                          • 10. Re: Found a significant LR4 speedup - regenerate ACR cache
                            jfriend0 Level 1

                            B r e t t wrote:

                             

                            Adobe recommends ACR cache of "10gb or more"

                             

                            http://helpx.adobe.com/lightroom/kb/optimize-performance-lightroom.htm l

                            In practice how large an ACR cache you need would depend upon whether you work with RAW images, how big your RAW images are and what a typical working set of RAW images that you work with are (200, 500, 1000, etc...).  The more you process together, the larger a cache you would need.  I figure that 2x the max amount of images you ever import at a time is probably a good safe minimum to work on that particular shoot.  So, since I sometimes come near to filling up two 16GB cards in a big sports shoot, a safe min for me would be 2x16 x 2 = 64GB.  I set mine to 100GB.

                            • 11. Re: Found a significant LR4 speedup - regenerate ACR cache
                              Scooby007 Level 3

                              I was simply passing along what Adobe - the author of the software - recommends.

                               

                              I figure that 2x the max amount of images you ever import at a time is probably a good safe minimum to work on that particular shoot.  So, since I sometimes come near to filling up two 16GB cards in a big sports shoot, a safe min for me would be 2x16 x 2 = 64GB.  I set mine to 100GB.

                               

                              The cache is not the same size as the capture. It's about 2 or 3% of the size (e.g. 97% smaller). Your 100gb is enough for almost 350,000 photos.

                              • 12. Re: Found a significant LR4 speedup - regenerate ACR cache
                                ssprengel Adobe Community Professional & MVP

                                I would think your ACR cache be 3 to 4 times larger than the total size of all the RAW images you want to work with at a time.  I am saying that because the ACR cache contains the 3-colors-per-pixel versions of your 1-color-per-pixel RAW images and depending on if the data is compressed much if at all, it could be much larger than the RAW size of the corresponding image.  If you normally barely fill up a 2GB card with your RAWs, then a 5-8GB cache might be ok.  If you fill up a 32-GB card, then a 100-150GB cache would be ok.

                                • 13. Re: Found a significant LR4 speedup - regenerate ACR cache
                                  Scooby007 Level 3

                                  I would think your ACR cache be 3 to 4 times larger than the total size of all the RAW images you want to work with at a time.  I am saying that because the ACR cache contains the 3-colors-per-pixel versions of your 1-color-per-pixel RAW images and depending on if the data is compressed much if at all, it could be much larger than the RAW size of the corresponding image.

                                   

                                  The cache is 97% smaller than the capture, not 3 to 4 times larger. Average cache size is 350kb. Just look on your HDD.

                                   

                                  If you fill up a 32-GB card, then a 100-150GB cache would be ok.

                                   

                                  If you fill up a 32gb card you need about 400mb for the acr cache in LR