Oracle8i Internal Services for Waits, Latches, Locks, and Memory

This concise book contains detailed information about Oracle internals -- information that's not readily available to Oracle customers. It lays a foundation for advanced performance tuning of the Oracle database. Based on Oracle8i release 8.1, the book describes many of the secrets of Oracle's internal services: data structures, algorithms, and undocumented Oracle system statistics. Main topics include: Waits - how Oracle processes communicate via semaphores, and how to use the Oracle wait statistics to identify the source of performance problems. Latches - how they keep multiple processes from inspecting protected data structures at the same time, and how to examine and control latch behavior and statistics. Locks - how they work with latches to protect data structures (locks allow multiple sessions to share resources in some cases), and how locks affect performance. There is also a detailed discussion of instance locks, which are used in parallel server environments. Memory - how Oracle uses memory (e.g., the various elements of the System Global Area), and how Oracle dynamically allocates and manages memory. Oracle8i Internal Services is aimed especially at administrators and developers who need detailed internal information to do advanced performance tuning. The book will expand your repertoire of tuning solutions and troubleshooting techniques by explaining how you can use Oracle's hidden parameters and undocumented system statistics to best advantage.

Autorentext

Steve Adams runs a small consulting company, Ixora, that specializes in advanced Unix and Oracle performance tuning. He is based in Sydney, Australia, but also works remotely for clients in America and Europe. Steve is a regular contributor to various Oracle discussion forums on the Internet, where he is widely regarded as the leading performance expert. His experience with Oracle dates back to version 3 (1984). However, most of his work has been in Unix performance tuning. His interest in Oracle--and Oracle internals in particular--was rekindled when working as the Unix performance expert on a benchmark of an Oracle-based application in 1995. He found the challenge of understanding Oracle performance to be extremely demanding, and yet irresistible. Steve doesn't yet claim to have mastered the topic of Oracle performance, but he does have plenty of insight to share. He can be contacted directly at steve.adams@ixora.com.au or via his company's web site at http: //www.ixora.com.au/.

Zusammenfassung
Based on Oracle8i, release 8.1, this text contains detailed information about Oracle internals (data structures, algorithms, hidden parameters, and undocumented system statistics). Main topics include wits, latches, locks and memory use and management.

Inhalt

Preface; Why This Book?; Warnings; Audience for This Book; About the APT Scripts; Conventions Used in This Book; Comments and Questions; Acknowledgments; Chapter 1: Introduction; 1.1 The Oracle Kernel Layers; 1.2 The Kernel Services; Chapter 2: Waits; 2.1 Semaphores; 2.2 Wait Statistics; 2.3 Reference; Chapter 3: Latches; 3.1 Latches and Locks; 3.2 Parent and Child Latches; 3.3 Latch Gets; 3.4 Advanced Latching Control; 3.5 Reference; Chapter 4: Locks; 4.1 Lock Usage; 4.2 Lock Modes; 4.3 Enqueue Locks; 4.4 Row Cache Enqueues; 4.5 Library Cache Locks and Pins; 4.6 DML Locks; 4.7 Buffer Locks; 4.8 Sort Locks; 4.9 Reference; Chapter 5: Instance Locks; 5.1 The Lock Manager; 5.2 Global Locks; 5.3 PCM Instance Locks; 5.4 Other Instance Locks; 5.5 Reference; Chapter 6: Memory; 6.1 The SGA; 6.2 The Shared Pool; 6.3 Process Memory; 6.4 Reference; Colophon;