Performance Tuning AWR ADDM

AWR contains the  vital elapsed-time information on what happened during particular snapshot range.

Main sections of AWR report:

Report Summary
Cache Sizes
Load Profile
Instance Efficiency Percentages
Shared Pool Statistics
Top 5 Timed Events
Wait Events
Time Model Statistics
Operating System Statistics
Service Statistics
SQL Section
I/O Section
Buffer Wait Statistics            
SGA Memory Summary 

The script you can see at 

SQL> $ORACLE_HOME/rdbms/admin/awrrpt.sql


ADDM

ADDM analyzes the AWR report and generate the report and further action to be taken.

The types of problems that ADDM considers

CPU bottlenecks
Undersized Memory Structures
I/O capacity issues
High load SQL statements  
High load PL/SQL 
Database configuration issues 
Concurrency issues
Hot objects and top SQL

It also shows the information on:

• Hardware changes - Adding CPUs or changing the I/O subsystem configuration
  
• Database configuration - Changing initialization parameter settings
  
• Schema changes - Hash partitioning a table or index, or using automatic segment-space management (ASSM)
  
• Application changes - Using the cache option for sequences or using bind variables
  
• Using other advisors - Running the SQL Tuning Advisor on high load SQL or running the Segment Advisor on hot objects