Set the database to automatic memory management
Setting up automatic memory management of the database is mainly about setting two parameters:
Memory_max_target
Memory_target
If these two parameters are set to 0, the database memory is managed manually, otherwise it is managed automatically.
Shut down the database.
SQL > startup nomount
ORA-00838: Specified value of MEMORY_TARGET is too small, needs to be at least 6384M
-- the reason why I reported an error here is my previous alter system set MEMORY_TARGET='1536M' scope='spfile'.
Because the memory allocated to SGA by the system before is only so large, the parameters I set must not exceed SGA, which is the reason for the error in restarting the database after modifying the parameters.
SQL > create pfile ='/ home/oracle/initora11g.ora' from spfile
File created.
Create the pfile file, and then modify the pfile file to set the size of these two parameters to 7G.
[oracle@TestServer dbhome_1] $vi / home/oracle/initora11g.ora
Atsdb.__db_cache_size=16777216
Atsdb.__java_pool_size=16777216
Atsdb.__large_pool_size=16777216
Atsdb.__oracle_base='/opt/app/oracle'#ORACLE_BASE set from environment
Atsdb.__pga_aggregate_target=5083496448
Atsdb.__sga_target=1610612736
Atsdb.__shared_io_pool_size=0
Atsdb.__shared_pool_size=1526726656
Atsdb.__streams_pool_size=16777216
* .audit_file_dest='/opt/app/oracle/admin/atsdb/adump'
* .audit_trail='db'
* .compatible='11.2.0.0.0'
* .control_files='/opt/app/oracle/oradata/atsdb/control01.ctl','/opt/app/oracle/flash_recovery_area/atsdb/control02.ctl'
* .db_block_size=8192
* .db_domain=''
* .db_name='atsdb'
* .db_recovery_file_dest='/opt/app/oracle/flash_recovery_area'
* .db_recovery_file_dest_size=4070572032
* .diagnostic_dest='/opt/app/oracle'
* .dispatchers=' (PROTOCOL=TCP) (SERVICE=atsdbXDB)'
* .global_names=FALSE
* .memory_max_target=7610612736
* .memory_target=7610612736
* .open_cursors=300
* .pga_aggregate_target=5078253568
* .processes=3000
* .remote_login_passwordfile='EXCLUSIVE'
* .sessions=3555
* .sga_target=1610612736
* .undo_tablespace='UNDOTBS1'
Start the database from pfile after the modification is complete:
SQL > ='/ home/oracle startup pfile/initora11g.ora'
ORACLE instance started.
Total System Global Area 7616245760 bytes
Fixed Size 2214496 bytes
Variable Size 6979323296 bytes
Database Buffers 603979776 bytes
Redo Buffers 30728192 bytes
Database mounted.
Database opened.
You can see that the database has been restarted because the parameters that were just modified in pfile are now synchronized to spfile:
SQL > create spfile from pfile='/home/oracle/initora11g.ora'
File created.
SQL > show parameter memory
NAME TYPE
VALUE
-
Hi_shared_memory_address integer
0
Memory_max_target big integer
7296M
Memory_target big integer
7296M
Shared_memory_address integer
0
SQL >
It can also be seen here that the database is now automatically managed in memory.
Success.
