We're experiencing a nasty issue in Oracle 11g Release 2 where the w3wp process takes over and entire processor core, and debugging shows that the Oracle data provider is throwing ThreadAbortExceptions infinitely. A developer found this issue by doing the following:
1) Browse a web site that uses Oracle data connections locally (http://localhost/OracleWebSite - we use IIS, not the ASP.NET dev server, for all of our sites). This ensures that the w3wp process is running and that an active Oracle pool of connections exists in the app pool.
2) Stop the web site (or perform a Rebuild All operation in Visual Studio on the web site in question).
Our Oracle connection handling in the affected applications (all Oracle web apps) is well-established and robust. This issue does not occur if we disable connection pooling. This issue does not occur in Oracle 11g Release 1.