Description:

This presentation is to explore and troubleshoot various customer performance issues encountered in RAC environment. A few discussion points: 1. Review and understanding of AWR reports/statspack reports to troubleshoot global cache performance issues. Trend analysis for global cache traffic and performance using AWR/statspack tables. Also review of simple techniques to probe interconnect performance. 2. Understanding wait events in SQL trace files related to RAC such as gc cr grant 2-way, gc cr grant 3-way, gc multi block reads, etc. 3. Global cache object re-mastering: object re-mastering, various parameters influencing object re-mastering, and how to use it to tune performance. Wait events associated with object re-mastering. 4. Global cache waits and LGWR performance. LGWR performance is important in single instance databases and LGWR performance is even more critical in RAC instances. Discussion about GC performance issues due to LGWR performance issues. 5. Interconnect issues, lost packets, and AWR statistics. Identifying interconnect issues with database and OS statistics. 6. Troubleshooting performance issues with MTU/jumbo frames and jumbo frames mis-configuration issues. 7. Troubleshooting RAC background processes such as LMS/LMD etc. 8. Troubleshooting parallel query, interconnect, and PQ setup related performance issues. 9. Concurrency-induced global cache issues and few time-tested simple work-arounds. 10. Troubleshooting locking issues in RAC environments. 11. Bind peeking issues and RAC instances.