HugePages on Linux: What It Is... and What It Is Not... (Doc ID 361323.1)
HugePages on Oracle Linux 64-bit (Doc ID 361468.1)
HugePages and Oracle Database 11g Automatic Memory Management (AMM) on Linux (Doc ID 749851.1)
Linux IA64 example of allocating 48GB SGA using hugepages (Doc ID 397568.1)
Shell Script to Calculate Values Recommended Linux HugePages / HugeTLB Configuration (Doc ID 401749.1)
USE_LARGE_PAGES To Enable HugePages In 11.2 (Doc ID 1392497.1)
你可以根据下面的语句查询当前的SGA和PGA的信息,并结合你实际的业务,去确定你们的SGA和PGA的大小。
The following SQL statements highlight what is happening:
SQL> select * from v$sgainfo where name like 'Maximum SGA%' or name like 'Free SGA%';
NAME BYTES RES
-------------------------------- ---------- ---
Maximum SGA Size 1068937216 No
Free SGA Memory Available 432013312
SQL> select component,current_size from v$memory_dynamic_components where component like '%Target%';
更多信息,可以参考下面的文档
Automatic PGA Memory Management (Doc ID 223730.1)
Use Automatic Shared Memory Management (Doc ID 270065.1)
SGA and PGA Management in 11g's Automatic Memory Management (AMM) (Doc ID 1392549.1)
但是实际禁用memory_max_target和memory_target参数需要注意:
官方文档说的是“unset” ,直接alter system set memory_target=0 scope=spfile;是更改不成功的。直接设置为‘0’,就抱如下的错误
ORA-00843: Parameter not taking MEMORY_MAX_TARGET into account
ORA-00849: SGA_TARGET 35433480192 cannot be set to more than MEMORY_MAX_TARGET 0.
ORA-01078: failure in processing system parameters