Oracle | DBMS_HEAT

Oracle DBMS_HEAT_MAP Version 26ai

General Information

Library Note

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Oracle Database 26ai will be available on generic Linux platforms in January and soon on AIX and Windows

Purpose This package provides heatmap information at block/extent/segment object and tablespace levels. The package contains the definitions for processing heatmap for top N objects and tablespaces.

The execution privilege is granted to PUBLIC. Procedures in this package run under the caller security. The user must have ANALYZE privilege on the object.

AUTHID CURRENT_USER

Data Types TYPE hm_bls_record IS RECORD ( owner VARCHAR2(128), segment_name VARCHAR2(128), partition_name VARCHAR2(128), tablespace_name VARCHAR2(30), file_id NUMBER, relative_fno NUMBER, block_id NUMBER, writetime DATE); TYPE hm_bls_row IS TABLE OF hm_bls_record; TYPE hm_bls_tabidx IS TABLE OF hm_bls_record INDEX BY PLS_INTEGER; TYPE hm_els_record IS RECORD ( owner VARCHAR2(128), segment_name VARCHAR2(128), partition_name VARCHAR2(128), tablespace_name VARCHAR2(30), file_id NUMBER, relative_fno NUMBER, block_id NUMBER, blocks NUMBER, bytes NUMBER, min_writetime DATE, max_writetime DATE, avg_writetime DATE); TYPE hm_els_row IS TABLE OF hm_els_record; TYPE hm_els_tabidx IS TABLE OF hm_els_record INDEX BY PLS_INTEGER; TYPE hm_object_row IS RECORD ( owner VARCHAR2(100), segment_name VARCHAR2(100), partition_name VARCHAR2(100), tablespace_name VARCHAR2(100), segment_type VARCHAR2(20), segment_size NUMBER, min_writetime DATE, max_writetime DATE, avg_writetime DATE, min_readtime DATE, max_readtime DATE, avg_readtime DATE, min_ftstime DATE, max_ftstime DATE, avg_ftstime DATE, min_lookuptime DATE, max_lookuptime DATE, avg_lookuptime DATE); TYPE hm_object_table IS TABLE OF hm_object_row; TYPE hm_object_tabidx IS TABLE OF hm_object_row INDEX BY PLS_INTEGER; TYPE hm_tablespace_row IS RECORD ( tablespace_name VARCHAR2(30), segment_count NUMBER, allocated_bytes NUMBER, min_writetime DATE, max_writetime DATE, avg_writetime DATE, min_readtime DATE, max_readtime DATE, avg_readtime DATE, min_ftstime DATE, max_ftstime DATE, avg_ftstime DATE, min_lookuptime DATE, max_lookuptime DATE, avg_lookuptime DATE); TYPE hm_tablespace_table IS TABLE OF hm_tablespace_row; TYPE hm_tablespace_tabidx IS TABLE OF hm_tablespace_row INDEX BY PLS_INTEGER;

Dependencies

ALL_HEAT_MAP_SEGMENT	DBA_LOBS	SEG$
ALL_HEAT_MAP_SEG_HISTOGRAM	DBA_SEGMENTS	SYS_DBA_SEGS
ALL_OBJECTS	DBA_TABLES	USER_HEAT_MAP_SEGMENT
CDB_HEATMAP_TOP_OBJECTS	DBA_TABLESPACES	USER_HEAT_MAP_SEG_HISTOGRAM
CDB_HEATMAP_TOP_TABLESPACES	DBA_TABLESPACE_USAGE_METRICS	USER_TABLESPACES
CDB_HEAT_MAP_SEGMENT	DBMS_HEAT_MAP_INTERNAL	V$HEAT_MAP_SEGMENT
CDB_HEAT_MAP_SEG_HISTOGRAM	DBMS_PRIV_CAPTURE	WRI$_HEATMAP_TOPN_DEP1
DBA_HEATMAP_TOP_OBJECTS	DBMS_SPACE	WRI$_HEATMAP_TOPN_DEP2
DBA_HEATMAP_TOP_TABLESPACES	DBMS_STANDARD	WRI$_HEATMAP_TOP_OBJECTS
DBA_HEAT_MAP_SEGMENT	HEAT_MAP_EXTENT_STAT$	WRI$_HEATMAP_TOP_TABLESPACES
DBA_HEAT_MAP_SEG_HISTOGRAM	HEAT_MAP_STAT$	WRI$_TOPN_METADATA
DBA_INDEXES	PLITBLM

Documented Yes: Packages and Types Reference

First Available 12.1

Initialization Parameter ALTER SESSION SET heat_map = <OFF | ON>; ALTER SYSTEM SET heat_map = <OFF | ON> SCOPE=<BOTH | MEMORY | SPFILE> ....;

ALTER SESSION SET heat_map = ON;

      

      ALTER SYSTEM SET heat_map = on SCOPE=BOTH SID='*';

Security Model Owned by SYS with execute granted to PUBLIC. To run the user must have the ANALYZE privilege on the object.

Source {ORACLE_HOME}/rdbms/admin/dbmsspu.sql

Subprograms

AUTO_ADVISOR_HEATMAP_JOB	EXTENT_HEAT_MAP	SEGMENT_HEAT_MAP
BLOCK_HEAT_MAP	OBJECT_HEAT_MAP	TABLESPACE_HEAT_MAP

AUTO_ADVISOR_HEATMAP_JOB

Advisor job to materialize heat maps dbms_heat_map.auto_advisor_heatmap_job(topn IN NUMBER DEFAULT 100);

exec dbms_heat_map.auto_advisor_heatmap_job;

      

      SELECT * FROM wri$_heatmap_top_tablespaces;

      

      SELECT * FROM wri$_heatmap_top_objects;

BLOCK_HEAT_MAP

Returns the block level ILM statistics for a table segment. It returns no information for segment types that are not data. The stat returned today is the latest modification time of the block. dbms_heat_map.block_heat_map( owner IN VARCHAR2, segment_name IN VARCHAR2, partition_name IN VARCHAR2 DEFAULT NULL, sort_columnid IN NUMBER DEFAULT NULL, sort_order IN VARCHAR2 DEFAULT NULL) RETURN hm_bls_row PIPELINED;

SELECT * FROM TABLE(dbms_heat_map.block_heat_map('SYS', 'OBJ$'));

      

      SELECT relative_fno, block_id

      FROM TABLE(dbms_heat_map.block_heat_map('SYS', 'OBJ$'));

EXTENT_HEAT_MAP

Returns the extent level ILM statistics for a table segment. It returns no information for segment types that are not data. Aggregates at extent level including minimum modification time and maximum modification time are returned. dbms_heat_map.extent_heat_map( owner IN VARCHAR2, segment_name IN VARCHAR2, partition_name IN VARCHAR2 DEFAULT NULL) RETURN hm_els_row PIPELINED;

SELECT * FROM TABLE(dbms_heat_map.extent_heat_map('SYS', 'SOURCE$'));

      

      SELECT relative_fno, block_id, blocks, bytes

      FROM TABLE(dbms_heat_map.extent_heat_map('SYS', 'SOURCE$'));

OBJECT_HEAT_MAP

Returns the minimum, maximum and average access times for all the segments belonging to the object. The object must be a table. dbms_heat_map.object_heat_map( object_owner IN VARCHAR2, object_name IN VARCHAR2) RETURN hm_object_table PIPELINED;

SELECT * FROM TABLE(dbms_heat_map.object_heat_map('SYS', 'SOURCE$'));

      

      SELECT tablespace_name, segment_name, segment_type, segment_size, avg_readtime, max_lookuptime

      FROM TABLE(dbms_heat_map.object_heat_map('SYS', 'SOURCE$'));

SEGMENT_HEAT_MAP

Returns the heatmap attributes for a named segment dbms_heat_map.segment_heat_map( tablespace_id IN NUMBER, header_file IN NUMBER, header_block IN NUMBER, segment_objd IN NUMBER, min_writetime OUT DATE, max_writetime OUT DATE, avg_writetime OUT DATE, min_readtime OUT DATE, max_readtime OUT DATE, avg_readtime OUT DATE, min_ftstime OUT DATE, max_ftstime OUT DATE, avg_ftstime OUT DATE, min_lookuptime OUT DATE, max_lookuptime OUT DATE, avg_lookuptime OUT DATE);

conn / as sysdba

      

      SELECT tablespace_name, header_file, header_block

      FROM dba_segments

      WHERE segment_name = 'SOURCE$';

      

      SELECT ts#

      FROM ts$

      WHERE name = 'SYSTEM';

      

      SELECT data_object_id

      FROM dba_objects

      WHERE object_name = 'SOURCE$';

      

      DECLARE

       minwr  DATE;

       maxwr  DATE;

       avgwr  DATE;

       minrd  DATE;

       maxrd  DATE;

       avgrd  DATE;

       minfts DATE;

       maxfts DATE;

       avgfts DATE;

       minlu  DATE;

       maxlu  DATE;

       avglu  DATE;

      BEGIN

        dbms_heat_map.segment_heat_map(0, 1, 2296, 294, minwr, maxwr, avgwr, minrd, maxrd, avgrd, minfts, maxfts, avgfts, minlu, maxlu, avglu);

      

        dbms_output.put_line(minwr);

        dbms_output.put_line(maxwr);

        dbms_output.put_line(avgwr);

        dbms_output.put_line(minrd);

        dbms_output.put_line(maxrd);

        dbms_output.put_line(avgrd);

        dbms_output.put_line(minfts);

        dbms_output.put_line(maxfts);

        dbms_output.put_line(avgfts);

        dbms_output.put_line(minlu);

        dbms_output.put_line(maxlu);

        dbms_output.put_line(avglu);

      END;

      /

TABLESPACE_HEAT_MAP

Returns the minimum, maximum and average access times for all the segments in the tablespace dbms_heat_map.tablespace_heat_map(tablespace_name IN VARCHAR2) RETURN hm_tablespace_table PIPELINED;

conn / as sysdba

      

      SELECT * FROM TABLE(dbms_heat_map.tablespace_heat_map('SYSTEM'));

      

      SELECT segment_count, allocated_bytes

      FROM TABLE(dbms_heat_map.tablespace_heat_map('SYSTEM'));