database advisors automatic database diagnostic monitor ( addm )

Database Advisors

Automatic Database Diagnostic Monitor (ADDM)

Database Advisors


SQL Tuning Advisor

Database Advisors


SQL Tuning Advisor

SQL Access Advisor

Database Advisors


SQL Tuning Advisor

SQL Access Advisor

Memory Advisor

Database Advisors


SQL Tuning Advisor

SQL Access Advisor

Memory Advisor

Segment Advisor

Database Advisors


SQL Tuning Advisor

SQL Access Advisor

Memory Advisor

Segment Advisor

Undo Advisor


Hardware Issues

CPU Bottlenecks

Excessive Parsing

Buffer Sizing

Connection Management

Real Application Cluster

ADDM Setup

Enabled at Database Creation

STATISTICS_LEVEL (TYPICAL or ALL)

DBIO_EXPECTED (Hardware Specific)

Snap Shot Once an Hour

Runs Against AWR

Diagnosing Database Performance Issues with ADDM

Invoke Automatic Database Diagnostic Monitor (ADDM):

From Oracle Enterprise Manager (OEM)

From SQL prompt

Analyze results:Manually using $ORACLE_HOME/rdbms/admin/addmrpt.sql script

Using DBMS_ADVISOR package

Running ADDM using DBMS_ADVISOR APIs

Create advisor task (CREATE_TASK)


Create advisor task (CREATE_TASK)Set required task parameters (SET_TASK_PARAMETER)START_SNAPSHOTEND_SNAPSHOTDB_IDINSTANCEDBMI_EXPECTED



Execute task (EXECUTE_TASK)



Execute task (EXECUTE_TASK)Create report (GET_TASK_REPORT)



Execute task (EXECUTE_TASK)Create report (GET_TASK_REPORT)View tasks (DBA_ADVISOR_TASKS)

SQL Access Advisor

Analyze Schema Design

ScenariosSingle Statements

Multiple Statement Workloads

Recommendations Evaluated in Context

Ran with No Impact


DBMS_ADVISOR.CREATE_TASK

DBMS_ADVISOR.CREATE_SQLWKLD

DBMS_ADVISOR.ADD_SQLWKLD_REF

DBMS_ADVISOR.EXECUTE_TASK

DBMS_ADVISOR.GET_TASK_SCRIPT

Memory Advisor

Access Information Through OEM

Disabled with Automatic Memory Tuning

Segment Advisor

Identifies Segments with Reclaimable Space

Scheduled Runs by Default

Capable of Manual Runs

Objects Selected Tablespaces with Space Issues

Most Active Segments

Highest Growth Rate Segments

Manual Run of Segment Advisor

Create Task

Assign Object to Task

Set Task ParameterTime_limit

Recommend_all

Executing the Task

View ResultsOEM

DBA_ADVISOR_* views

SQL Tuning Advisor

SQL Structure Analysis

Access Path Analysis

Statistics Analysis

SQL Profiling

Manual SQL Tuning Advisor Runs

DBMS_SQLTUNE.CREATE_TUNING_TASK

DBMS_SQLTUNE.EXECUTE_TUNING_TASK

DBMS_SQLTUNE.REPORT_TUNING_TASK

SQL Tuning Sets (STS)

One or More SQL Statements

Loaded from AWR, Cursor Cache, User




Change Analysis with Contextual Information

User Schema

List of Bind Values

Basic Statistics

Execution Plans




Change Analysis with Contextual Information

User Schema

List of Bind Values

Basic Statistics

Execution Plans

Transportable across databases

What is Undo Retention

Maintains Old Committed Data

Used for Read Consistency

Used for Flashback Features

Undo Retention Tuning

Length of Time (s)

Evaluation

Fixed Undo Tablespace Size• Usage Statistics• Undo Tablespace Size• Current System Load

AUTOEXTEND• Longest-Running Query• UNDO_RETENTION parameter

Viewing Undo Retention Period

Query V$UNDOSTAT for last four days of data

Query DBA_HIST_UNDOSTAT to go back beyond last four days

database advisors automatic database diagnostic monitor ( addm )

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