Force.com IDE Developer Guide

Get Started with the Force.com IDE
Develop with the Force.com IDE
Test Code with the Force.com IDE
Deploy Code with the Force.com IDE
Get Started with the Apex Debugger
Get Started with the Apex Debugger
Set Up the Apex Debugger
Explore a Simple Debugging Puzzle
Manage Debugging Sessions
Apex Debugger Limits and Considerations
Apex Debugger Troubleshooting
Relaunch Your Debug Configuration
Kill an Orphaned Session
Change Your Session Timeout Preference
Report Drastic Issues to Customer Support
Force.com IDE Release Notes
Useful References
PDF

Report Drastic Issues to Customer Support

It’s unlikely that you’ll encounter drastic issues while working with the Apex Debugger. However, never say never. If you encounter performance issues or are unable to kill your orphaned sessions, contact Salesforce Customer Support for help. If necessary, Support can kill all debugging sessions for the instance on which your org is running. This process prevents you—and all orgs running on your instance—from immediately initiating new debugging sessions.