I've upgraded from LR5 to LR6 on OS X Yosemite 10.10.3 with Mid 2014 Macbook Pro with Geforce750M and then I tried to import about 15,000 photo and video with the new catalog without any changes in configuration. But LR6 was significant slow so it's still working but imported about 300 files during the night - about 9 hour. So I uninstalled LR6 and LR5 again and tried to import. LR5 completed whole the photo importing in about 10 min. I did remove catalog file also didn't changed any option/setting after install LR6. But LR6 was too slow to import files. I can't say it's importing correctly. What's the problem in my case? If it's not solved, I have to ask return LR6 since I can't do anything with it.
Thanks in advance,
No need to re-import from LR5 to LR6, just open the LR5 catalog in LR6 and follow the prompts to upgrade the catalog.
That could be a solution but I'd like to know why this situation was occurred. In case of using LR6 without migration from LRX, I'll encounter this issue with the latest LR6.