After recently updating to Safari 4.01 and OS X 10.5.7, all of a sudden I had all very bad Safari performance — including constant freeze situations. After being ready to delete the impacted user, I realized that there were some issues with the database.sqlite3 file in the Library ? PubSub ? Database folder. The PubSub folder is used for tracking RSS feeds, and it seems my problem resided there.
Safari 4.01 + Mac OS X 10.5.7 にしてから、不安定になったりパフォーマンスが落ちたなぁと感じたら試しにやってみるといいです。
2. `~/Library/PubSub/Database/Database.sqlite3` をゴミ箱へ