OCP-1Z0-053-V12.02-417题

417.When manually configuring the SGA, which of the following parameter changes requires an instance restart to take effect?

A. DB_CACHE_SIZE

B. SHARED_POOL_SIZE

C. LARGE_POOL_SIZE

D. JAVA_POOL_SIZE

E. SGA_MAX_SIZE

F. SORT_AREA_SIZE

Answer: E

答案解析：

sys@TEST1107> desc v$sgainfo

 Name                                                  Null?    Type

 ----------------------------------------------------- -------- ------------------------------------

 NAME                                                          VARCHAR2(32)

 BYTES                                                          NUMBER

 RESIZEABLE                                               VARCHAR2(3)

 RESIZEABLE  为YES，则可以在线更改，及时生效，如果为NO，则只能重启生效。

sys@TEST1107> select * from v$sgainfo;

NAME                                  BYTES RES

-------------------------------- ---------- ---

Fixed SGA Size                      2227984 No

Redo Buffers                        8847360 No

Buffer Cache Size                 352321536 Yes

Shared Pool Size                  335544320 Yes

Large Pool Size                    16777216 Yes

Java Pool Size                     16777216 Yes

Streams Pool Size                  16777216 Yes

Shared IO Pool Size                       0 Yes

Granule Size                       16777216 No

Maximum SGA Size                 1269366784 No

Startup overhead in Shared Pool    97589480 No

Free SGA Memory Available         520093696

12 rows selected.

sys@TEST1107> alter system set sga_max_size=1200M;

alter system set sga_max_size=1200M

                 *

ERROR at line 1:

ORA-02095: specified initialization parameter cannot be modified

sys@TEST1107> alter system set sga_max_size=1200M scope=spfile;

System altered.

如果不加scope，则不能修改，如果加了scope=spfile，意味着重启后生效。

sys@TEST1107> alter system set large_pool_size=20M;

System altered.

sys@TEST1107> select * from v$sgainfo;

NAME                                  BYTES RES

-------------------------------- ---------- ---

Fixed SGA Size                      2227984 No

Redo Buffers                        8847360 No

Buffer Cache Size                 335544320 Yes

Shared Pool Size                  335544320 Yes

Large Pool Size                    33554432 Yes

Java Pool Size                     16777216 Yes

Streams Pool Size                  16777216 Yes

Shared IO Pool Size                       0 Yes

Granule Size                       16777216 No

Maximum SGA Size                 1269366784 No

Startup overhead in Shared Pool    97589480 No

Free SGA Memory Available         520093696

12 rows selected.