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Oracle 内存顾问
--查看内存相关参数
SYS@ test10g> col name for a30
SYS@ test10g> col value for a20
SYS@ test10g> select name, value
from v$parameter
where name in(‘sga_max_size‘,
‘db_cache_size‘,
‘shared_pool_reserved_size‘,
‘large_pool_size‘,
‘java_pool_size‘,
‘db_block_size‘,
‘db_block_buffers‘,
‘log_buffer‘,
‘sort_area_retained_size‘,
‘hash_area_size‘,
‘sessions‘,
‘open_cursors‘,
‘streams_pool_size‘,
‘sga_target‘,
‘pga_aggregate_target‘)
order by name;
NAME VALUE
------------------------------ --------------------
db_block_buffers 0
db_block_size 8192
db_cache_size 0
hash_area_size 131072
java_pool_size 0
large_pool_size 0
log_buffer 2879488
open_cursors 300
pga_aggregate_target 68157440
sessions 170
sga_max_size 314572800
sga_target 314572800
shared_pool_reserved_size 5872025
sort_area_retained_size 0
streams_pool_size 0
--查看PGA实际大小
SQL> select sum(value) from v$sesstat
natural join v$statname
where name=‘session pga memory‘;
SUM(VALUE)
----------
45710324
--查看SGA实际大小
SQL> select sum(bytes) from v$sgastat;
SUM(BYTES)
----------
314574992
--查看sga分配
SYS@ test10g> col COMPONENT for a30;
SYS@ test10g> select t.component, t.current_size/1024/1024 "current_size (MB)"
from v$sga_dynamic_components t;
COMPONENT current_size (MB)
------------------------------ -----------------
shared pool 112
large pool 4
java pool 32
streams pool 0
DEFAULT buffer cache 148
KEEP buffer cache 0
RECYCLE buffer cache 0
DEFAULT 2K buffer cache 0
DEFAULT 4K buffer cache 0
DEFAULT 8K buffer cache 0
DEFAULT 16K buffer cache 0
DEFAULT 32K buffer cache 0
ASM Buffer Cache 0
SQL> col value for 9999999999999999
SQL> select * from v$sga;
NAME VALUE
------------------------------ -----------------
Fixed Size 1220360
Variable Size 150995192
Database Buffers 369098752
Redo Buffers 2973696
--shared pool建议（手动管理时）
select t.shared_pool_size_for_estimate "SP",
t.estd_lc_size "EL",
t.estd_lc_memory_objects "ELM",
t.estd_lc_time_saved "ELT",
t.estd_lc_time_saved_factor "ELTS%",
t.estd_lc_memory_object_hits "ELMO"
from v$shared_pool_advice t;
SP EL ELM ELT ELTS% ELMO
---------- ---------- ---------- ---------- ---------- ----------
52 12 1203 2176 .9918 48822
64 23 2481 2194 1 49437
76 30 3831 2194 1 49446
88 30 3831 2194 1 49446
100 30 3831 2194 1 49446
112 30 3831 2194 1 49446
124 30 3831 2194 1 49446
136 30 3831 2194 1 49446
148 30 3831 2194 1 49446
160 30 3831 2194 1 49446
172 30 3831 2194 1 49446
184 30 3831 2194 1 49446
196 30 3831 2194 1 49446
208 30 3831 2194 1 49446
220 30 3831 2194 1 49446
232 30 3831 2194 1 49446
--buffer cache 建议（手动管理时）
select size_for_estimate "target M",
buffers_for_estimate,
estd_physical_read_factor "physical_read %",
estd_physical_reads
from v$db_cache_advice
where name=‘DEFAULT‘
and block_size=(select value from v$parameter
where name=‘db_block_size‘)
and advice_status=‘ON‘;
target M BUFFERS_FOR_ESTIMATE physical_read % ESTD_PHYSICAL_READS
---------- -------------------- --------------- -------------------
12 1497 2.6352 20265
24 2994 1.8889 14526
36 4491 1.7167 13201
48 5988 1.0333 7946
60 7485 1 7690
72 8982 1 7690
84 10479 1 7690
96 11976 1 7690
108 13473 1 7690
120 14970 1 7690
132 16467 1 7690
144 17964 1 7690
148 18463 1 7690
156 19461 1 7690
168 20958 1 7690
180 22455 1 7690
192 23952 1 7690
204 25449 1 7690
216 26946 1 7690
228 28443 1 7690
240 29940 .9981 7676
--PGA顾问
SQL> select pga_target_for_estimate,pga_target_factor,estd_extra_bytes_rw
from v$pga_target_advice;
PGA_TARGET_FOR_ESTIMATE PGA_TARGET_FACTOR ESTD_EXTRA_BYTES_RW
----------------------- ----------------- -------------------
17039360 .25 0
34078720 .5 0
51118080 .75 0
68157440 1 0
81788928 1.2 0
95420416 1.4 0
109051904 1.6 0
122683392 1.8 0
136314880 2 0
204472320 3 0
272629760 4 0
408944640 6 0
545259520 8 0
已选择14行。
--SGA顾问
SQL> select sga_size,sga_size_factor,estd_db_time
from v$sga_target_advice;
SGA_SIZE SGA_SIZE_FACTOR ESTD_DB_TIME
---------- --------------- ------------
300 1 72
150 .5 72
225 .75 72
600 2 71
450 1.5 71
525 1.75 71
375 1.25 71
已选择8行。
--AMM顾问 11g
select * from v$memory_target_advice order by memory_size;
MEMORY_SIZE MEMORY_SIZE_FACTOR ESTD_DB_TIME ESTD_DB_TIME_FACTOR VERSION
----------- ------------------ ------------ ------------------- ----------
300 .5 705 1.0845 0
450 .75 650 1 0
600 1 650 1 0
750 1.25 650 1 0
900 1.5 650 1 0
1050 1.75 650 1 0
1200 2 650 1 0
Oracle 内存顾问