Oracle調整SGA大小

Oracle 11g 只要設置 memory 就可以了。不需要單獨對 sga_max_size 進行設置，
設置memory_max_target、memory_target  一般原則是 物理內存的1/2。設好了重啟實例，sga_max_size 將自動變成memory_max_target設置的值

memory_max_target < shm 切記，否則Oracle實例將啟動失敗，報

ORA-00845: MEMORY_TARGET not supported on this system 錯，點擊查看shm設置

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SQL> show parameter sga

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
lock_sga boolean FALSE
pre_page_sga boolean FALSE
sga_max_size big integer 512M
sga_target big integer 512M
SQL>

SQL> show parameter memory

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
hi_shared_memory_address integer 0
memory_max_target big integer 0
memory_target big integer 0
shared_memory_address integer 0
SQL>


sql>alter system set memory_max_target = 15G scope=spfile;
sql>alter system set memory_target = 15G scope=spfile;

shutdown immediate
startup

SQL> show parameter memory

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
hi_shared_memory_address integer 0
memory_max_target big integer 15G
memory_target big integer 15G
shared_memory_address integer 0
SQL>