CHAPTER 01
🏗️
Oracle Architecture
Diagnose instance health, SGA/PGA configuration, memory modes, background processes and session waits.
SGAPGADBWRLGWRMemory
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CHAPTER 02
⏱️
Wait Events & Performance Model
Analyse top wait events, identify bottlenecks using the time-based tuning model, and drill into the most expensive waits.
ASHAWRWait ClassesDB Time
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CHAPTER 03
🧠
SQL Optimizer
Diagnose bad execution plans, stale statistics, bind variable issues, hard parses and SQL plan regressions.
Execution PlansCBOStatisticsHints
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CHAPTER 04
📇
Indexing
Find missing indexes, unused indexes, clustering factor problems, and conditions silently preventing index use.
B-treeClustering FactorInvisible IndexFTS
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CHAPTER 05
💾
Memory Tuning
Diagnose buffer cache hit ratio, shared pool fragmentation, PGA spills, ORA-04031 root causes and memory advisor output.
Buffer CacheShared PoolPGA AdvisorHugePages
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CHAPTER 06
💿
I/O & Storage
Find hot datafiles, diagnose redo log bottlenecks, TEMP tablespace issues, checkpoint pressure and async I/O settings.
Redo LogsDatafilesTEMPCheckpoints
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CHAPTER 07
🔒
Locking & Contention
Diagnose blocking sessions, deadlocks, enqueue waits, latch contention, missing FK indexes and sequence bottlenecks.
TX LocksDeadlocksLatchesEnqueues
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