This is a common problem. As of today, you cannot disable the logging. What many of us do is clear out that table every so many minutes. The querying isn't the issue as mySQL is designed for that. It's the storing that becomes the problem. That table can easily fill up with millions of rows, causing your site to slow down tremendously. Thus, clearing it every few minutes resolves this. Search the forum for this issue as there are tuns of posts on how to setup a script to clear it automatically.