Aperture 3 library performance tip after upgrading

Question

This tip may be helpful for anyone experiencing slow project/album loading and beachballing even with no background processes running in aperture 3.
I was having some major issues with performance in aperture 3 with all library/project/album and book loading operations. It was very odd because Adjustment performance is very good.
All my imported aperture 2 books would beach ball for about 50 seconds to load, and then each page would take 10 seconds to load after clicking on it. In comparison my aperture 2 library was near instantaneous.
After exporting the project as a separate library, rebuilding the library, repairing permissions, nothing was working.
As a last ditch effort before opening up Shark - I decided to open up the library in the finder, and manually delete all of the original previews. I then opened up the library in aperture and manually updated all the previews by highlighting all the thumbnails and right clicking -> update previews.
Once this process completed I quit aperture and restarted to see if I was still getting any slowdowns and the problem is now gone! Library loading and project switching operations are speedy as ever now, and the book navigation is faster than aperture 2 now.
Hope this helps anyone with performance issues.

Answer 1

Speak up if anyone has problems migrating because of previews or is successful in migrating without previews. I suspect this is my problem. I get to:
Upgrading Library 7% complete (updating master metadata - 5,068 remaining)
After restoring from a file vault with Aperture 2, I get to the same spot, with or without previews. Although this is a slightly different issue, I tried deleting previews within Aperture and reimporting. I got to the same exact spot as before. The computer becomes nearly unresponsive, and I have to force quit Aperture after hours of sitting at 5,068 remaining.