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Contents
Send Us Your Comments.................................................................................................................. vii
Preface............................................................................................................................................................ ix

1 Performance Overview

Performance Terms............................................................................................................................. 1-2
What is Performance Tuning?.......................................................................................................... 1-2
Response Time.............................................................................................................................. 1-3
System Throughput...................................................................................................................... 1-4
Wait Time....................................................................................................................................... 1-4
Critical Resources......................................................................................................................... 1-5
Effects of Excessive Demand....................................................................................................... 1-6
Adjustments to Relieve Problems.............................................................................................. 1-6
Setting Performance Targets............................................................................................................. 1-7
Setting User Expectations.................................................................................................................. 1-7
Evaluating Performance .................................................................................................................... 1-7
Performance Methodology ............................................................................................................... 1-8
Factors in Improving Performance............................................................................................ 1-9
Architecture........................................................................................................................................ 1-10

2 Monitoring Your Web Server

Monitoring Processor Use................................................................................................................. 2-2
Using the sar Utility (AIX, HP-UX, Intel Solaris)..................................................................... 2-2
Using the top Utility..................................................................................................................... 2-3