Since upgrading from version 8.x to 9.x, debugging has become slower in Toad in the same environment. Using a 64bit AIX machine. Using the JDWP will be slower than using the DBMS.
1. Ensure user has access to DBA views and use the following option: View | Toad Options ... | Startup | Check for Access to DBA Views
2. Ensure collect statistics on the Database. Refer to the following link: <http://asktoad.com/DWiki/doku.php/faq/answers/database_versions?s=gather>
3. Turn the SQL history Tab OFF with the following option: Use F8 to disable the SQL history tab and select View | Toad Options ... | Editor | Code Assist | SQL Recall window to reduce the amount of statements to save.
4. Select Help | Toad Advisor and check for an warnings
5. Install an instant client (e.g. 10g) on the client machine, if possible and use it to connect to database.
Waiting for fix in a future version of Toad for Oracle.