[bbk4956]第65集 第7章 - 数据库的维护 02

SQL> select tablespace_name,contents from dba_tablespaces;

TABLESPACE_NAME                CONTENTS
------------------------------ ---------
SYSTEM                         PERMANENT
SYSAUX                         PERMANENT
UNDOTBS1                       UNDO
TEMP                           TEMPORARY
USERS                          PERMANENT
EXAMPLE                        PERMANENT
TAB_U2                         PERMANENT
TAB_U3                         PERMANENT
TS0                            PERMANENT
TS1                            PERMANENT
TS2                            PERMANENT

TABLESPACE_NAME                CONTENTS
------------------------------ ---------
TS3                            PERMANENT
TS4                            PERMANENT
FBDA_TBS                       PERMANENT

14 rows selected.

tablespace_name SYSAUX ，系统辅助表空间，AWR（Automatic Workload Reponsitory）的信息就是存放在此表空间中.

system build-in user SYSMAN,AWR的数据，就是属于SYSMAN的.

Automatic Workload Repository(AWR)自动负荷信息库

• Built-in reponsitory of perform perfomance
• Snapshots of database metrics taken every 60 minutes and retained for eight day.
• Foundation for all self-management functions

AWR Infrastructure

AWR Baselines

Enterprise Manager and the AWR

Managing the AWR

• Retention period
  • Default:Eight days
  • Consider storage needs
• Collection interval
  • Default:60 minutes
  • Consider storage needs and performance impact
• Collection level
  • Base(disable most ADDM functionality)
  • Typical(recommended)
  • All(adds addtional SQL tunning information to snapshots)

实际业务需求：假如有新的应用添加，新应用的SQL执行性能需要监控，此时就可以将collection level调整为ALL（假设之前是typical）,等新的应用调整、磨合的差不多了，相对稳定了，就可以将collection level 调整为typical.

Statistics Levels