E-Book Overview
Yes, the book was written when Oracle 8i was around, but it is well worth the read even today. Adams knows how Oracle works and explains the waits, latches and locks pretty well. I especially liked the chapter on Memory. I learned a lot from this book. This was money well spent. Highly recommended.
E-Book Content
Oracle8i Internal Services for Waits, Latches, Locks, and Memory Steve Adams Publisher: O'Reilly
First Edition October 1999 ISBN: 1-56592-598-X, 132 pages Buy Print Version
Copyright Table of Contents Index Full Description About the Author Reviews Colophon Examples Reader reviews Errata
Based on Oracle8i, release 8.1, this concise book contains detailed, hard-to-find information about Oracle internals (data structures, algorithms, hidden parameters, and undocumented system statistics). Main topics include waits, latches, locks (including instance locks used in parallel server environments), and memory use and management. Aimed especially at readers doing advanced performance tuning.
Oracle8i Internal Services for Waits, Latches, Locks, and Memory Copyright © 1999 O'Reilly & Associates, Inc. All rights reserved. Printed in the United States of America. Published by O'Reilly & Associates, Inc., 101 Morris Street, Sebastopol, CA 95472. Oracle® and all Oracle-based trademarks and logos are trademarks or registered trademarks of Oracle Corporation, Inc. in the United States and other countries. O'Reilly & Associates, Inc. is independent of Oracle Corporation. The O'Reilly logo is a registered trademark of O'Reilly & Associates, Inc. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and O'Reilly & Associates, Inc. was aware of a trademark claim, the designations have been printed in caps or initial caps. The use of the bumblebee image in association with Oracle8i internal services is a trademark of O'Reilly & Associates, Inc. While every precaution has been taken in the preparation of this book, the publisher assumes no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein.
Oracle8i Internal Services for Waits, Latches, Locks, and Memory Preface Why This Book? Warnings Audience for This Book About the APT Scripts Conventions Used in This Book Comments and Questions Acknowledgments 1. Introduction 1.1 The Oracle Kernel Layers 1.2 The Kernel Services 2. Waits 2.1 Semaphores 2.2 Wait Statistics 2.3 Reference 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 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 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 6. Memory 6.1 The SGA 6.2 The Shared Pool 6.3 Process Memory 6.4 Reference Colophon
Preface A few years ago, I set my heart on researching and writing a truly advanced Oracle performance-tuning book. Soon, I had a detailed outline running to more than thirty pages. But when I started to write, I began to realize how much I had yet to learn about Oracle. Each chapter was going to require considerably more research than I had at first imagined. In particular, I began to realize that an understanding of some aspects of Oracle internals would be vital to my quest. So I began to learn what I could of Oracle internals, starting with the X$ tables. If I had known then what I know now, about how vast an undertaking I was commencing, I would probably never have attempted it. And many times I would have given up in despair, except for the encouragement of my friends. They always be