a0108 oracle performance tuning and optimizatio morebook vn 9763

®

Oracle

Performance Tuning
and Optimization
Edward Whalen

201 West 103rd Street
Indianapolis, Indiana 46290

i


To
my father.
Oracle
Performance Tuning & Optimization

Acquisitions Editor

Copyright  1996 by Sams Publishing
FIRST EDITION
All rights reserved. No part of this book shall be reproduced, stored in a retrieval
system, or transmitted by any means, electronic, mechanical, photocopying,
recording, or otherwise, without written permission from the publisher. No patent
liability is assumed with respect to the use of the information contained herein.
Although every precaution has been taken in the preparation of this book, the
publisher and author assume no responsibility for errors or omissions. Neither is any
liability assumed for damages resulting from the use of the information contained
herein. For information, address Sams Publishing, 201 W. 103rd St., Indianapolis,

IN 46290.
International Standard Book Number: 0-672-30866-X
Library of Congress Catalog Card Number: 95-72345
99

98

97

96

4

3

2

Development Editors
Byron Pearce
Todd Bumbalough

Software Development
Specialist
Steve Flatt

Production Editor
Alice Martina Smith

Technical Reviewers
David Kennedy

Stephen Tallon

Editorial Coordinator

1

Bill Whitmer

Interpretation of the printing code: the rightmost double-digit number is the year of
the book’s printing; the rightmost single-digit, the number of the book’s printing.
For example, a printing code of 96-1 shows that the first printing of the book
occurred in 1996.
Composed in AGaramond and MCPdigital by Macmillan Computer Publishing
Printed in the United States of America

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Formatter
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have been appropriately capitalized. Sams Publishing cannot attest to the accuracy of
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Publisher and President:
Acquisitions Manager:

Development Manager:
Managing Editor:
Marketing Manager:

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Cover Designer
Tim Amrhein

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Book Designer
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Copy Writer
Peter Fuller

Production Team Supervisor
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Production

ii

Mary Ann Abramson
Georgianna Briggs
Jama Carter
Amy Chinn
Michael Dietsch
Jason Hand
Sonja Hart
Ayanna Lacey
Clint Lahnen
Paula Lowell
Brian-Kent Proffitt
Bobbi Satterfield
Susan Van Ness
Colleen Williams


Overview
PART I

1
2
3
4
5
6
7
PART II
8

9
10
11
12
13
14
15
PART III
16
17
18
19
20
21
22
23
PART IV
24
25
26
27
28
29
30
31
32

Introduction ............................................................................................ xxiv
Introduction 1
Introduction to Oracle ................................................................................. 3

Understanding Terms ................................................................................ 21
What Is a Well-Tuned System? .................................................................. 31
Tuning Methodology ................................................................................. 41
Benchmarking ........................................................................................... 51
Performance Monitoring Tools .................................................................. 73
Performance Engineering Starts at the Design Stage ................................... 81
Tuning the Server 89
What Affects Oracle Server Performance? ................................................... 91
Oracle Instance Tuning .............................................................................. 97
Performance Enhancements .................................................................... 139
Tuning the Server Operating System........................................................ 167
Operating System-Specific Tuning .......................................................... 177
System Processors .................................................................................... 205
Advanced Disk I/O Concepts .................................................................. 213
Disk Arrays .............................................................................................. 225
Configuring the System 243
OLTP System .......................................................................................... 245
Batch Processing System........................................................................... 265
Decision Support System ......................................................................... 285
Data Warehousing System........................................................................ 303
BLOB System .......................................................................................... 323
The Oracle Parallel Server System ............................................................ 339
Optimal Backup and Recovery ................................................................ 349
Miscellaneous Configurations .................................................................. 367
Tuning SQL 391
What Is a Well-Tuned SQL Statement? ................................................... 393
Using EXPLAIN PLAN and SQL Trace ......................................................... 403
Tuning SQL Statements........................................................................... 419
Using the Oracle Optimizer .................................................................... 437
Using Procedures, Functions, and Packages ............................................. 449

Providing for Data Integrity and Triggers ................................................. 461
Using Hints .............................................................................................. 475
Introducing SQL Development Tools ...................................................... 489
Miscellaneous SQL Topics ....................................................................... 501

iii


Oracle Performance Tuning & Optimization

PART V Tuning the Client 513

33
34
35
36
PART VI
37
38
PART VII
A
B
C
D
E
F

iv

What Affects Client Performance? ........................................................... 515

Tuning the Client System ........................................................................ 525
Using GUI Builders ................................................................................. 533
Using Middleware Products .................................................................... 555
Tuning the Network 563
What Affects Network Performance?........................................................ 565
Tuning the Network Components ........................................................... 573
References 579
Review of Tuning Guidelines .................................................................. 581
Quick Reference ...................................................................................... 595
Flowcharts ................................................................................................ 603
Glossary ................................................................................................... 607
Oracle Tuning Parameters ........................................................................ 619
Contents of the CD-ROM ....................................................................... 645
Index ....................................................................................................... 649


Contents
Introduction....................................................................................... xxiv
Part I Introduction 1

1 Introduction to Oracle ............................................................................ 3
The Database .............................................................................................. 4
The Physical Layer .................................................................................. 4
The Logical Layer .................................................................................... 5
The Oracle Instance ..................................................................................... 8
The Oracle Memory Structure ................................................................ 8
System Global Area (SGA) ...................................................................... 9
Program Global Area (PGA) ................................................................. 10
Processes ................................................................................................ 10
How Transactions Work ............................................................................ 12

Oracle Products ......................................................................................... 13
Oracle RDBMS Products ...................................................................... 13
Oracle Workgroup Server ..................................................................... 15
Personal Oracle for Windows ................................................................ 16
Oracle Development Tools ................................................................... 16
Oracle Applications ............................................................................... 17
Oracle Services ...................................................................................... 18
Summary.................................................................................................... 19
2 Understanding Terms ........................................................................... 21
Terms ........................................................................................................ 22
RDBMS Functionality ............................................................................... 26
Checkpoint ........................................................................................... 26
Logging and Archiving........................................................................... 26
Business Models ........................................................................................ 27
OnLine Transaction Processing (OLTP) ............................................... 27
Batch Processing .................................................................................... 27
Decision Support .................................................................................. 28
Data Warehousing ................................................................................. 28
Binary Large Objects (BLOBs) .............................................................. 28
Unit Conversions ....................................................................................... 28
Powers of 10 ......................................................................................... 29
Storage Units ........................................................................................ 29
Summary.................................................................................................... 30
3 What Is a Well-Tuned System? ............................................................. 31
Client/Server Computing ........................................................................... 32
The Client or Front-End Machines ....................................................... 33
The Server ............................................................................................ 33
The Network ........................................................................................ 35
Client/Server Checklist .......................................................................... 35

v


virtual memory

memory
buffer cache, 107-108
operating system, 99
private PL/SQL
areas, 100
private SQL areas, 100
shared pool, 100-106
methodology, 44
analyzing results, 50
determing solution to
problems, 48-49
examining system for
problems, 45-46
finding cause or
performance problems,
47-48
goal setting for optimal
performance, 48-50
performance
clients, 85
networks, 85-86
servers, 85
Tuxedo systems, features,
344
two-phase commit, 617

two-tiered system
architecture, 556

U
UNIQUE constraint, 465
unique indexes, 149, 427
units of measurements,
conversions, 28
binary storage units, 29-30
powers of 10, 29
UNIX, 530-531
architecture, 192
development of, 191
I/O subsystem, 197-198
asynchronous I/O,
198-200
file system, 198
raw device interface, 198
memory, 192-193, 531
reducing unnecessary
memory usage, 193

SGA tuning, 194-195
user capacity, 195-196
networks, 196, 531
SCO UNIX, 196-197
Solaris, 197
tuning, 575
UnixWare, 197
new features

benchmarking, 200
cache affinity, 202
disabling preemptive
scheduling, 201
ISM (Intimate Shared
Memory), 201
load balancing, 202
post-wait semaphores,
201
parameters
asynchronous I/O, 198
SHMMAX, 194
SHMSEG, 194
summary of tuning
guidelines, 202-203
UNIX SVR4, 191
UnixWare
buffer cache, tuning, 193
networks, 197
parameters
asynchronous I/O, 199
shared memory, 194-195
updatable snapshots, 374
UPDATE statement
defined, 617
execution plan, displaying
with EXPLAIN PLAN
command, 414-416
updating rollback
segments, 128

USE_CONCAT hint,
483-484
USE_MERGE hint, 484
USE_NL hint, 485
user processes (client
processes), 10
user-transaction profile,
flowchart, 605
USER_CONS_COLUMNS
view, 467

USER_CONSTRAINTS
view, 467
USER_DUMP_DEST
parameter, 405, 637
USER_TRIGGERS view, 471

V
V$FILESTAT dynamic
performance table, disk
access information, 597
V$LATCH dynamic
performance table, latch
contention data, 601
V$ROLLSTAT dynamic
performance table, dynamic
rollback growth data, 600
V$ROLLSTAT table,
rollback segment data, 129
V$ROWCACHE table, data

dictionary statistics, 103
V$SYSSTAT dynamic
performance table,
recursive calls data, 599
V$SYSSTAT table, buffer
cache statistics, 107
V$WAITSTAT dynamic
performance table, rollback
contention data, 599
V$WAITSTAT table,
rollback segment data, 127
validating data, triggers, 469
VARCHAR2 data type, 510
variables, binding, 401
viewing
constraints, 467-469
triggers, 471-472
views
defined, 6, 617
dynamic performance
tables, 74-75
virtual memory
defined, 25, 211, 617
paging, 24, 211
swapping, 25, 211

681


warehouses

W-X-Y-Z
warehouses, see data
warehouses
WebServer system
archive logs, 389
block
buffers, 388
size, 389
characteristics, 386-387
checkpoints, 389
clusters, 389
contention, latch and
rollback, 389
defined, 18, 368, 386
design considerations,
387-388
enhancements, 389-390
hash clusters, 389
library cache, 388

682

multiblock reads, 389
Parallel Query option, 389
Parallel Server option, 389
spin counts, 388
summary, 390
tuning considerations,
388-389

Windows 3.1
memory, 528
networks, 528-529
Windows 95
32-bit support, 529-530
memory, 530
networks, 530
Oracle support, 530
Windows for Workgroups
3.11
memory, 528
networks, 528-529

Windows NT, 183
16-bit applications, 527
architecture, 183-184
defined, 527
I/O performance, 528
I/O subsystem, 186-187
memory, 185, 527
reducing unnecessary
memory usage, 185
SGA tuning, 185-186
user capacity, 186
networks, 186
tuning, 575
summary of tuning
guidelines, 187
threads, 184
words, 29

Workgroup Server, 15-16
write caches, disk arrays,
228-229