17 Replies Latest reply on Mar 16, 2016 10:42 AM by Victoria Bampton LR Queen

    Only one core?!

    BramvanOosterhout Level 1

      Hi, I am making a timelaps and now am I exporting all of the pictures for the timelaps.

      But there is a problem, I have a Intel core i7 5820K CPU but Lightroom does only use one core!

       

      This is a big problem for me, I have six cores and he is using only one core. So my export is 6 times slower!

      m5oEbdU.png

        • 1. Re: Only one core?!
          cppasm Level 3

          This is done for purpose so you can comfortably use LR while exporting.

          If you want increase performance and maximize CPU load you should divide your image set into smaller packs and run several exports simultaneously.

          For maximum load you should have number of exports running in parallel equal or greater than number of logical CPU cores (12 in your case).

          • 2. Re: Only one core?!
            johnrellis Most Valuable Participant

            Are you on LR 5 or earlier? LR 6 export was changed to take advantage of multiple processors, and most people find it counter-productive to run more than one export at a time.

            • 3. Re: Only one core?!
              BramvanOosterhout Level 1

              I am on the latest Lightroom but I found a kind of fix, juist export the project in 6 'exports' and the LR exports them on all the cores.

              Sad solution but yeah, I hope Adobe will fix these things.

              • 4. Re: Only one core?!
                johnrellis Most Valuable Participant

                [Update: I misread your last post.  I'll provide an updated response below.]

                • 5. Re: Only one core?!
                  D Fosse Adobe Community Professional & MVP

                  If only one virtual core is used, something's wrong on that system.

                   

                  Lr has been multi-core optimized for a long time. This is an old screenshot for a Lr5 export, on an i7-3820:

                  D800_export.png

                  • 6. Re: Only one core?!
                    johnrellis Most Valuable Participant

                    While versions 5 and earlier did use multiple cores for export, in general LR didn't do it very effectively, and there were many complaints on the official Adobe feedback forum: Lightroom: Make use of extra cores to process multiple photos in parallel | Photoshop Family Customer Community. Many people resorted to manually kicking off multiple exports as a workaround, a tip that Scott Kelby repeated on his Web site. Rob Cole even had a plugin that automated this.


                    LR CC 2015 / 6 was changed to use multiple cores more effectively; for example, see this quote from Victoria Bampton's blog: "Export speed has been improved, and it makes better use of multiple cores so you don’t have to manually queue up multiple exports."  And for at least some people, CC 2015 / 6 is too aggressive in using multiple cores for exports, causing problems with interactive response in the UI: Lightroom 6 / CC2015: Very slow UI response with background export(s) running | Photoshop Family Customer Community

                    • 7. Re: Only one core?!
                      johnrellis Most Valuable Participant

                      [I misread your last post; here's my updated reply.]

                      just export the project in 6 'exports' and the LR exports them on all the cores. Sad solution but yeah, I hope Adobe will fix these things.

                      This was a common workaround for LR 5 and earlier, but it shouldn't be necessary for CC 2015 / 6.  Please do Help > System Info and report the exact version you're running.

                       

                      For example, here's the CPU history for an export of 100 files on my LR CC 2015.4 / OS X 10.11 system:

                      Screen Shot 2016-03-13 at 3.50.33 PM.png

                      • 8. Re: Only one core?!
                        Victoria Bampton LR Queen Adobe Community Professional & MVP

                        johnrellis wrote:

                        LR CC 2015 / 6 was changed to use multiple cores more effectively; for example, see this quote from Victoria Bampton's blog: "Export speed has been improved, and it makes better use of multiple cores so you don’t have to manually queue up multiple exports."  And for at least some people, CC 2015 / 6 is too aggressive in using multiple cores for exports, causing problems with interactive response in the UI: Lightroom 6 / CC2015: Very slow UI response with background export(s) running | Photoshop Family Customer Community

                         

                        It was, and then part of those improvements were undone again in an update (6.3?) as it was conflicting with an ACR optimisation which was also trying to speed things up.

                        • 9. Re: Only one core?!
                          trshaner Adobe Community Professional & MVP

                          Victoria Bampton LR Queen wrote:

                           

                          It was, and then part of those improvements were undone again in an update (6.3?) as it was conflicting with an ACR optimisation which was also trying to speed things up.

                          I'm using LR CC 2015.4 on Windows 7 64 bit with an i7-860 Quad Core processor and seeing all eight virtual-cores used on Exports. Actual CPU Usage varies from about 25% to 100% or about 50% Average. No issues here...I wouldn't want any higher CPU usage! It's possible only OS X systems are affected.

                           

                          Export Core Usage - LR CC 2015.4.jpg

                          • 10. Re: Only one core?!
                            D Fosse Adobe Community Professional & MVP

                            And let's not forget disk I/O is limiting at some point too. All that data needs to go somewhere.

                            • 11. Re: Only one core?!
                              BramvanOosterhout Level 1

                              Here is a screenshot of my version of Adobe LR and the specs of my PC.

                              I have LR installed on my Samsung 950 Pro SSD so that can not be the bottleneck, I also in/exported the images from another SSD.

                               

                              But the problem is a kind of fixed.

                              f3efcd33124e7bcd019eee3509c9b8fa.png

                              • 12. Re: Only one core?!
                                johnrellis Most Valuable Participant
                                It's possible only OS X systems are affected.

                                Not in general -- see my previous post, showing similar CPU usage on OS X as what you observed on Windows.

                                • 13. Re: Only one core?!
                                  johnrellis Most Valuable Participant
                                  And let's not forget disk I/O is limiting at some point too.

                                  I think on typical exports of raw files to full-size JPEGs, disk i/o is not a limiting factor.  For example, on my 2.8 GHz Intel Core i7 Macbook Pro, when exporting many raw files that are about 20 MB each to JPEGs that are about 7 MB each, disk I/O averages roughly 8 MB/s read and 4 MB/s written, and these are large, sequential reads and writes.  This is an order-of-magnitude less than the throughput of a typical personal computer's spinning disk, much less an SSD.

                                  • 14. Re: Only one core?!
                                    johnrellis Most Valuable Participant
                                    It was, and then part of those improvements were undone again in an update (6.3?) as it was conflicting with an ACR optimisation which was also trying to speed things up.

                                    Interesting and good to know -- it wasn't documented in the release notes of 6.2, 6.3, or 6.4

                                     

                                    I just did a quickie test, and it doesn't appear that this affected export's overall utilization of multiple cores.  When doing one export of many raw files to large JPEGs, my CC 2015.4 / 2.8 GHz Macbook Pro does 0.37 photos/sec.  When doing two exports simultaneously, it does 0.42 photos/sec, only 14% faster. That is, there is little advantage to doing two simultaneous exports,   In previous versions of LR, there was a big advantage in doing two or three exports simultaneously.

                                    • 15. Re: Only one core?!
                                      Victoria Bampton LR Queen Adobe Community Professional & MVP

                                      johnrellis wrote:

                                      Interesting and good to know -- it wasn't documented in the release notes of 6.2, 6.3, or 6.4

                                       

                                      It was listed as a bug fix "Significant performance problems when exporting multiple photos".  It's a few months ago now, but essentially, 6.2 added an ACR optimisation which conflicted with the 6.0 export optimisation, causing hangs and other performance problems.  The 6.0 one got rolled back in 6.3 and the 6.2 change stayed.  I remember Jim Wilde (tng) doing a number of tests on the timings, so he's probably the expert on this one.

                                      • 16. Re: Only one core?!
                                        johnrellis Most Valuable Participant
                                        It was listed as a bug fix "Significant performance problems when exporting multiple photos".

                                        I just discovered that your list of bug fixes for 6.3 and 6.5 is more detailed than what Adobe published on blog.adobe.com.  I really appreciate your updates, but it seems a little weird that I have to go outside of Adobe to find out what bugs were fixed!  Thanks again.

                                        • 17. Re: Only one core?!
                                          Victoria Bampton LR Queen Adobe Community Professional & MVP

                                          The bug reports themselves should get updated shortly. Most big companies seem to only highlight their headline bug fixes.  No idea why!