Two Lightroom performance tips for you today:

• Optimize your library regularly. On a Mac, go to “Lightroom”, “Catalog Settings..”, and select “Relaunch and Optimize”.
• Increase your Camera RAW Cache size to at least 10 GB (if your hard disk has that much size available). On a Mac, go to “Lightroom”, “Preferences”, and set Camera Cache size to 10 GB or more.

This will keep your Lightroom installation working more quickly.