How I avoid "Faces" slow response in Aperture 3?

I bought Aperture 3 for my new Mac mini server, and I expect Aperture 3 can help me to manage my 60000 photos.

When I enable "Faces" to recognize people in my photos, I found Aperture become slower and slower.
Every time I confirm a known face, a color ball will show and Aperture will stop response for 5 seconds or more.

Not only in this main "Faces" screen, but also when I try "Confirm Faces" and click "Done".

Aperture will show "Searching for faces" at status bar for few seconds.
This problem almost let me give up using Aperture 3 Faces until I accidentally found solution.

To avoid such annoying lag problem, I need to input the name in the search bar of "Faces" main screen as following, watch the red arrows:

Then I try to execute "Confirm Faces", I found the working flow become smoother and shorter waiting time between scenes, especially the waiting time of "Searching for faces".

The more faces you had recognized, the more improvement you will see.