ORACLE 12C 内存手动和自动管理的切换

一、手动管理内存改为自动管理内存

ALTER SYSTEM SET MEMORY_TARGET = 10240M SCOPE=SPFILE;       #MEMORY_TARGET小于等于memory_max_target，二者均为0时为 手动管理内存
ALTER SYSTEM SET memory_max_target = 15000M SCOPE=SPFILE;

ALTER SYSTEM SET SGA_TARGET = 0 SCOPE=SPFILE;              #SGA_TARGET和PGA_AGGREGATE_TARGET为0时  为自动管理内存
ALTER SYSTEM SET SGA_MAX_SIZE=800M SCOPE=SPFILE;

ALTER SYSTEM SET PGA_AGGREGATE_TARGET = 0 SCOPE=SPFILE;
alter system set pre_page_sga=FALSE scope=spfile;    #启动实例时，不加载全部SGA

二、自动管理内存改为手动管理内存

ALTER SYSTEM SET MEMORY_TARGET = 0 SCOPE=SPFILE;       #MEMORY_TARGET小于等于memory_max_target，二者均为0时为 手动管理内存
ALTER SYSTEM SET memory_max_target = 0 SCOPE=SPFILE;

ALTER SYSTEM SET SGA_TARGET = 1024M SCOPE=SPFILE;              #SGA_TARGET和PGA_AGGREGATE_TARGET为0时  为自动管理内存
ALTER SYSTEM SET SGA_MAX_SIZE=2048M SCOPE=SPFILE;

ALTER SYSTEM SET PGA_AGGREGATE_TARGET = 512M SCOPE=SPFILE;
alter system set pre_page_sga=TRUE scope=spfile;    #启动实例时，加载SGA全部物理内存。