| Christian Antognini
Trivadis |
About Since 1995, Christian Antognini has focused on understanding how the Oracle database engine works. His main interests include logical and physical database design, the integration of databases with Java applications, the query optimizer and basically everything else related to application performance management and optimization. He is currently working as a principal consultant and trainer at Trivadis in Zürich, Switzerland. If Christian is not helping one of his customers get the most out of Oracle, he is somewhere lecturing on application performance management or new Oracle Database features for developers. In addition to classes and seminars organized by Trivadis, he regularly presents at conferences and user-group meetings. He is a proud member of the Trivadis Performance Team and of the OakTable Network. Christian is the author of the book Troubleshooting Oracle Performance (Apress, 2008). |
| Website/Blog |
Video |
| Track: ORA | |
Session title |
Session description |
Diagnosing Parallel Executions Performance |
The purpose of parallel executions is to distribute the execution of a single SQL statement over several sessions executed by several CPUs. There are, naturally, advantages and disadvantages to this. The main advantage is related to performance. In fact, provided that necessary resources are available, response time might be dramatically reduced. The main disadvantage is that the diagnosis of performance problems is more difficult. This is mainly due to the fact that Oracle's instrumentation is mostly implemented at the session level. As a result, the challenge is to correctly aggregate information coming from several sessions in order to fully describe how a SQL statement is being executed. The aim of this presentation is to describe how to find, aggregate and interpret execution plans and statistics coming from V$ views such as active session history and SQL trace. |
SQL Plan Baselines |
A SQL plan baseline is an object associated with a SQL statement that is designed to influence the query optimizer while it generates execution plans. As of Oracle Database 11g, SQL plan baselines substitute stored outlines. Actually, they can be considered an enhanced version of stored outlines. The aim of this presentation is to explain what SQL plan baselines are, how to create and manage them, and when to use them. |