[20190507]sga_target=0注意修改_kghdsidx_count設定.txt

--//昨天遇到一例檢視定義太複雜導致長時間分析sql語句出現library cache lock等待事件的情況.

--//加上大量使用非繫結變數語句,導致硬解析增加,導致問題更加嚴重.

--//順便解析當時同事發現僅僅1個CPU特別忙.實際上因為僅僅1個shared pool latch在工作.

1.環境:

> @ ver1

PORT_STRING VERSION BANNER

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

IBMPC/WIN_NT-8.1.0 10.2.0.3.0 Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - Prod

--//注32位版本.

2.解析:

SELECT addr

,latch#

,child#

,level#

,name

,gets

,sleeps

,immediate_gets

,immediate_misses

,spin_gets

FROM V$LATCH_CHILDREN

WHERE name LIKE 'shared pool'

ORDER BY addr;

ADDR LATCH# CHILD# LEVEL# NAME GETS SLEEPS IMMEDIATE_GETS IMMEDIATE_MISSES SPIN_GETS

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

05AA3858 213 1 7 shared pool 25235287 182 0 0 7384

05AA38C0 213 2 7 shared pool 151 0 0 0 0

05AA3928 213 3 7 shared pool 151 0 0 0 0

05AA3990 213 4 7 shared pool 151 0 0 0 0

05AA39F8 213 5 7 shared pool 151 0 0 0 0

05AA3A60 213 6 7 shared pool 151 0 0 0 0

05AA3AC8 213 7 7 shared pool 151 0 0 0 0

7 rows selected.

--//僅僅1個shared pool latch在使用.

> show parameter sga_

NAME TYPE VALUE

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

sga_max_size big integer 1200M

sga_target big integer 1200M

> @　hide _kghdsidx_count

NAME DESCRIPTION DEFAULT_VALUE SESSION_VALUE SYSTEM_VALUE

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

_kghdsidx_count max kghdsidx count TRUE 1 1

> @ hide _enable_shared_pool_durations

NAME DESCRIPTION DEFAULT_VALUE SESSION_VALUE SYSTEM_VALUE

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

_enable_shared_pool_durations temporary to disable/enable kgh policy TRUE TRUE TRUE

> show parameter cpu_count

NAME TYPE VALUE

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

cpu_count integer 16

--//注:在工作管理員看到32個CPU.不過我發現圖中下面一排16個cpu好像沒有負載.

--//主要問題是引數_kghdsidx_count=1.僅僅1個subpool.看來這個版本按照每個子緩衝池至少為512MB設計的.

--//引數_kghdsidx_count大小由CPU數量以及共享池大小決定的.最大不過7個.

--//我僅僅知道的原則:

--//共享子緩衝池的分配的演算法很簡單：

--//·每個子緩衝池必須滿足一定的記憶體約束；

--//·每4顆CPU可以分配一個子緩衝池，最多7個。

--//本來oracle這樣做為了減少shared pool,但是帶來另外的問題,如果每個子池太小,反而出現ora-04031錯誤.於是oracle限制每個子池

--//的大小,你可以發現一些blog提到減少引數_kghdsidx_count大小,限制每個子池避免出現子池太小的情況.

--//在Oracle 9i中，每個SubPool至少128MB，在Oracle 10g中，每個子緩衝池至少為256MB,在Oracle 11g中，每個子緩衝池至少為512MB.

--//Oracle 10g會將單個緩衝池分割再細分4個子分割槽進行管理(這可能是因為通常4顆CPU才分配一個SubPool),

--//分別是"instance", "session", "cursor", and "execution".

--//對方安裝32位系統,不能設定很大sga,受限共享記憶體大小600M上下,這樣僅僅1個shared pool latch.

--//這樣在大量硬解析的情況下,特別在分析sql語句很長時間的情況下僅僅1個shared pool latch自然很忙.

--//也就是同事看到的情況,僅僅1個CPU在忙...而且sql語句中的檢視關聯的表太多,導致1條sql語句消耗共享池很大,我執行前面的語句,檢視

--//v$sqlarea的SHARABLE_MEM達到512K.這樣大量非繫結變數語句導致許多物件退出又再進入共享池.

--//這就好比一個賓館的前臺僅僅1名接待人員一樣,客戶入住登記少沒有問題,一旦大量客戶登記入住,1個人自然忙不過來,

--//而其他人根本插不上手.有時候非常像現實工作的場景,1個忙的要死,別人根本插不上手,只能在那乾等^_^.

3.突然想起我以前1個測試:

--//[20190104]sga_target 的設定和ORA-04031錯誤.txt => http://blog.itpub.net/267265/viewspace-2305567/

--//發現一個問題,就是設定sga_target=0,如果大量語句不使用繫結變數可能存在問題.引數_kghdsidx_count=1,僅僅1個shared pool latch.

--//這樣情況應該適當增加_kghdsidx_count,透過測試說明問題:

$ export ORACLE_SID=xxxx

$ cat initxxxx.ora

db_name=xxxx

instance_name=xxxx

sga_target=0

sga_max_size=20G

--//設定sga_target=0.

SYS@xxxx> startup nomount

ORACLE instance started.

Total System Global Area 2.1379E+10 bytes

Fixed Size 2262656 bytes

Variable Size 2.1206E+10 bytes

Database Buffers 134217728 bytes

Redo Buffers 36073472 bytes

SELECT addr

,latch#

,child#

,level#

,name

,gets

,sleeps

,immediate_gets

,immediate_misses

,spin_gets

FROM V$LATCH_CHILDREN

WHERE name LIKE 'shared pool'

ORDER BY addr;

ADDR LATCH# CHILD# LEVEL# NAME GETS SLEEPS IMMEDIATE_GETS IMMEDIATE_MISSES SPIN_GETS

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

000000006010F288 336 1 7 shared pool 1397 0 0 0 5

000000006010F328 336 2 7 shared pool 0 0 0 0 0

000000006010F3C8 336 3 7 shared pool 0 0 0 0 0

000000006010F468 336 4 7 shared pool 0 0 0 0 0

000000006010F508 336 5 7 shared pool 0 0 0 0 0

000000006010F5A8 336 6 7 shared pool 0 0 0 0 0

000000006010F648 336 7 7 shared pool 0 0 0 0 0

7 rows selected.

SYS@xxxx> @ hide _kghdsidx_count

old 10: and lower(a.ksppinm) like lower('%&1%')

new 10: and lower(a.ksppinm) like lower('%_kghdsidx_count%')

NAME DESCRIPTION DEFAULT_VALUE SESSION_VALUE SYSTEM_VALUE

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

_kghdsidx_count max kghdsidx count TRUE 1 1

SYS@xxxx> @ hide _enable_shared_pool_durations

old 10: and lower(a.ksppinm) like lower('%&1%')

new 10: and lower(a.ksppinm) like lower('%_enable_shared_pool_durations%')

NAME DESCRIPTION DEFAULT_VALUE SESSION_VALUE SYSTEM_VALUE

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

_enable_shared_pool_durations temporary to disable/enable kgh policy TRUE FALSE FALSE

--//注意_enable_shared_pool_durations引數,在sga_target=0的情況下,_enable_shared_pool_durations的預設值等於FALSE(實際上設

--//置為true也無效,看後面測試)

--//也就是僅僅1個subpool,下面僅僅一個子子池.

SYS@xxxx> @ sgastatx.sql 'free memory'

-- All allocations:

SUBPOOL BYTES MB

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

shared pool (0 - Unused): 67108864 64

shared pool (1): 268435456 256

shared pool (Total): 335544320 320

-- Allocations matching "free memory":

old 15: AND LOWER(ksmssnam) LIKE LOWER('%&1%')

new 15: AND LOWER(ksmssnam) LIKE LOWER('%free memory%')

SUBPOOL NAME SUM(BYTES) MB

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

shared pool (0 - Unused): free memory 67108864 64

shared pool (1): free memory 30813880 29.39

--//僅僅1個子池.共享記憶體不足的情況下會從shared pool (0 - Unused)分過來.

--//另外注意1個問題,有一些文章提示查詢x$kghlu可以查詢這些子緩衝池的分配,我的測試不行,當然我現在sga_target=0的情況下不存

--//在子子池的情況.

--//透過一個內部表X$KGHLU([K]ernel [G]eneric memory [H]eap manager State of [L]R[U] Of Unpinned Recreatable chunks)可以

--//查詢這些子緩衝池的分配： (我的測試不行!!)

SYS@xxxx> select * from x$kghlu;

ADDR INDX INST_ID KGHLUIDX KGHLUDUR KGHLUSHRPOOL KGHLUFSH KGHLUOPS KGHLURCR KGHLUTRN KGHLUMXA KGHLUMES KGHLUMER KGHLURCN KGHLURMI KGHLURMZ KGHLURMX KGHLUNFU KGHLUNFS

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

00007F6D32E5EFF0 0 1 1 0 1 0 64 3 43 2147483647 0 0 0 0 0 0 0 0

--//只能透過heapdump轉儲獲取這方面資訊.

SYS@xxxx> alter session set events 'immediate trace name heapdump level 2';

Session altered.

$ grep 'sga heap' /u01/app/oracle/diag/rdbms/xxxx/xxxx/trace/xxxx_ora_43866.trc

HEAP DUMP heap name="sga heap" desc=0x60001190

HEAP DUMP heap name="sga heap(1,0)" desc=0x6005c318

--//可以看出問題.僅僅1個子池,不細分子子池.也就是在sga_target=0的情況下,可能需要手工設定_kghdsidx_count的大小.

--//不然可能出現shared pool latch的爭用,特別在應用沒有繫結變數的情況下.

--//我個人建議sga_target=0的情況下手工設定shared_pool_size,db_cache_size.

--//或者sga_target<>0的情況下,也設定shared_pool_size,db_cache_size作為最小值,避免記憶體在這些元件中變換.

--//修改*._kghdsidx_count=3

$ cat initxxxx.ora

db_name=xxxx

instance_name=xxxx

#sga_target=20G

sga_target=0

sga_max_size=20G

#pre_page_sga=true

*._kghdsidx_count=3

SYS@xxxx> startup nomount

ORA-04031: unable to allocate 320032 bytes of shared memory ("shared pool","unknown object","KGSK scheduler","KGSK chg class latches")

--//shared_pool_size太小.僅僅320M.

--//測試增加*._kghdsidx_count=3,*.shared_pool_size=1600M,*._enable_shared_pool_durations=true的情況:

$ cat initxxxx.ora

db_name=xxxx

instance_name=xxxx

sga_target=0G

#sga_target=20G

sga_max_size=20G

#pre_page_sga=true

*._kghdsidx_count=3

*.shared_pool_size=1600M

*._enable_shared_pool_durations=true

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

SYS@xxxx> startup nomount

ORACLE instance started.

Total System Global Area 2.1379E+10 bytes

Fixed Size 2262656 bytes

Variable Size 2.1206E+10 bytes

Database Buffers 134217728 bytes

Redo Buffers 36073472 by

SYS@xxxx> @ hide _kghdsidx_count

old 10: and lower(a.ksppinm) like lower('%&1%')

new 10: and lower(a.ksppinm) like lower('%_kghdsidx_count%')

NAME DESCRIPTION DEFAULT_VALUE SESSION_VALUE SYSTEM_VALUE

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

_kghdsidx_count max kghdsidx count FALSE 3 3

SYS@xxxx> @ hide _enable_shared_pool_durations

old 10: and lower(a.ksppinm) like lower('%&1%')

new 10: and lower(a.ksppinm) like lower('%_enable_shared_pool_durations%')

NAME DESCRIPTION DEFAULT_VALUE SESSION_VALUE SYSTEM_VALUE

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

_enable_shared_pool_durations temporary to disable/enable kgh policy FALSE TRUE TRUE

SYS@xxxx> select * from x$kghlu;

ADDR INDX INST_ID KGHLUIDX KGHLUDUR KGHLUSHRPOOL KGHLUFSH KGHLUOPS KGHLURCR KGHLUTRN KGHLUMXA KGHLUMES KGHLUMER KGHLURCN KGHLURMI KGHLURMZ KGHLURMX KGHLUNFU KGHLUNFS

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

00007FC432A52F70 0 1 3 0 1 0 20 0 14 2147483647 0 0 0 0 0 0 0 0

00007FC432A54640 1 1 2 0 1 0 9 0 7 2147483647 0 0 0 0 0 0 0 0

00007FC432A53FF0 2 1 1 0 1 0 14 0 10 2147483647 0 0 0 0 0 0 0 0

--//僅僅3個子池.看不出子子池.

SYS@xxxx> alter session set events 'immediate trace name heapdump level 2';

Session altered.

$ grep 'sga heap' /u01/app/oracle/diag/rdbms/xxxx/xxxx/trace/xxxx_ora_43949.trc

HEAP DUMP heap name="sga heap" desc=0x60001190

HEAP DUMP heap name="sga heap(1,0)" desc=0x6005c318

HEAP DUMP heap name="sga heap(2,0)" desc=0x60065be0

HEAP DUMP heap name="sga heap(3,0)" desc=0x6006f4a8

--//可以發現設定即使_enable_shared_pool_durations=TRUE,在sga_target=0G的情況下也不會出現子子池的情況.

SYS@xxxx> @ sgastatx.sql 'free memory'

-- All allocations:

SUBPOOL BYTES MB

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

shared pool (0 - Unused): 1275068416 1216

shared pool (1): 134217728 128

shared pool (2): 134217728 128

shared pool (3): 134217728 128

shared pool (Total): 1677721600 1600

-- Allocations matching "free memory":

old 15: AND LOWER(ksmssnam) LIKE LOWER('%&1%')

new 15: AND LOWER(ksmssnam) LIKE LOWER('%free memory%')

SUBPOOL NAME SUM(BYTES) MB

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

shared pool (0 - Unused): free memory 1275068416 1216

shared pool (1): free memory 48797608 46.54

shared pool (2): free memory 34835672 33.22

shared pool (3): free memory 48306064 46.07

SELECT addr

,latch#

,child#

,level#

,name

,gets

,sleeps

,immediate_gets

,immediate_misses

,spin_gets

FROM V$LATCH_CHILDREN

WHERE name LIKE 'shared pool'

ORDER BY addr;

ADDR LATCH# CHILD# LEVEL# NAME GETS SLEEPS IMMEDIATE_GETS IMMEDIATE_MISSES SPIN_GETS

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

000000006010F288 336 1 7 shared pool 732 0 1 0 0

000000006010F328 336 2 7 shared pool 673 0 1 0 0

000000006010F3C8 336 3 7 shared pool 903 0 1 0 1

000000006010F468 336 4 7 shared pool 1 0 0 0 0

000000006010F508 336 5 7 shared pool 1 0 0 0 0

000000006010F5A8 336 6 7 shared pool 1 0 0 0 0

000000006010F648 336 7 7 shared pool 1 0 0 0 0

7 rows selected.

--//總之,如果手工管理記憶體,設定sga_target=0G的情況下,適當設定_kghdsidx_count,shared_pool_size,db_cache_size值.

4.最後測試sga_target<>0的情況:

$ grep -v "^#" initxxxx.ora

db_name=xxxx

instance_name=xxxx

sga_target=20G

sga_max_size=20G

SYS@xxxx> @ hide _kghdsidx_count

old 10: and lower(a.ksppinm) like lower('%&1%')

new 10: and lower(a.ksppinm) like lower('%_kghdsidx_count%')

NAME DESCRIPTION DEFAULT_VALUE SESSION_VALUE SYSTEM_VALUE

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

_kghdsidx_count max kghdsidx count TRUE 6 6

SYS@xxxx> @ hide _enable_shared_pool_durations

old 10: and lower(a.ksppinm) like lower('%&1%')

new 10: and lower(a.ksppinm) like lower('%_enable_shared_pool_durations%')

NAME DESCRIPTION DEFAULT_VALUE SESSION_VALUE SYSTEM_VALUE

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

_enable_shared_pool_durations temporary to disable/enable kgh policy TRUE TRUE TRUE

SYS@xxxx> @ sgastatx.sql 'free memory'

-- All allocations:

SUBPOOL BYTES MB

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

shared pool (0 - Unused): 469762048 448

shared pool (1): 268435456 256

shared pool (2): 335544320 320

shared pool (3): 335544320 320

shared pool (4): 335544320 320

shared pool (5): 268435456 256

shared pool (6): 335544320 320

shared pool (Total): 2348810240 2240

8 rows selected.

-- Allocations matching "free memory":

old 15: AND LOWER(ksmssnam) LIKE LOWER('%&1%')

new 15: AND LOWER(ksmssnam) LIKE LOWER('%free memory%')

SUBPOOL NAME SUM(BYTES) MB

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

shared pool (0 - Unused): free memory 469762048 448

shared pool (1): free memory 207961376 198.33

shared pool (2): free memory 224686568 214.28

shared pool (3): free memory 270474992 257.95

shared pool (4): free memory 234357448 223.5

shared pool (5): free memory 206367112 196.81

shared pool (6): free memory 239940912 228.83

7 rows selected.

SYS@xxxx> select * from x$kghlu;

SUB SSUB FLUSHED LRU LIST RECURRENT TRANSIENT RESERVED RESERVED RESERVED RESERVED FREE UNPIN LAST FRUNP

ADDR INDX INST_ID POOL POOL KGHLUSHRPOOL CHUNKS OPERATIONS CHUNKS CHUNKS KGHLUMXA KGHLUMES KGHLUMER SCANS MISSES MISS SIZE MISS MAX SZ UNSUCCESS UNSUCC SIZE

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

00007F78519F2E48 0 1 6 0 1 0 17 0 17 2147483647 0 0 0 0 0 0 0 0

00007F78519F27F8 1 1 5 0 1 0 27 0 17 2147483647 0 0 0 0 0 0 0 0

00007F78519F3E60 2 1 4 0 1 0 23 0 19 2147483647 0 0 0 0 0 0 0 0

00007F78519F3810 3 1 3 0 1 0 40 0 16 2147483647 0 0 0 0 0 0 0 0

00007F78519F4EE0 4 1 2 0 1 0 34 0 22 2147483647 0 0 0 0 0 0 0 0

00007F78519F4890 5 1 1 0 1 0 26 0 16 2147483647 0 0 0 0 0 0 0 0

6 rows selected.

--// 看不出子子池的分配情況.

SYS@xxxx> alter session set events 'immediate trace name heapdump level 2';

Session altered.

$ egrep "sga heap|Total heap size" /u01/app/oracle/diag/rdbms/xxxx/xxxx/trace/xxxx_ora_44083.trc

HEAP DUMP heap name="sga heap" desc=0x60001190

HEAP DUMP heap name="sga heap(1,0)" desc=0x6005c318

Total heap size = 67108776

HEAP DUMP heap name="sga heap(1,1)" desc=0x6005db70

Total heap size = 67108776

HEAP DUMP heap name="sga heap(1,2)" desc=0x6005f3c8

Total heap size = 67108776

HEAP DUMP heap name="sga heap(1,3)" desc=0x60060c20

Total heap size = 67108776

--// 67108776*4/1024/1024 = 255.99966430664062500000 ,接近256M.

HEAP DUMP heap name="sga heap(2,0)" desc=0x60065be0

Total heap size =134217552

HEAP DUMP heap name="sga heap(2,1)" desc=0x60067438

Total heap size = 67108776

HEAP DUMP heap name="sga heap(2,2)" desc=0x60068c90

Total heap size = 67108776

HEAP DUMP heap name="sga heap(2,3)" desc=0x6006a4e8

Total heap size = 67108776

--//(134217552+67108776+67108776+67108776)/1024/1024 = 319.99958038330078125000,接近320M.

HEAP DUMP heap name="sga heap(3,0)" desc=0x6006f4a8

Total heap size =134217552

HEAP DUMP heap name="sga heap(3,1)" desc=0x60070d00

Total heap size = 67108776

HEAP DUMP heap name="sga heap(3,2)" desc=0x60072558

Total heap size = 67108776

HEAP DUMP heap name="sga heap(3,3)" desc=0x60073db0

Total heap size = 67108776

HEAP DUMP heap name="sga heap(4,0)" desc=0x60078d70

Total heap size =134217552

HEAP DUMP heap name="sga heap(4,1)" desc=0x6007a5c8

Total heap size = 67108776

HEAP DUMP heap name="sga heap(4,2)" desc=0x6007be20

Total heap size = 67108776

HEAP DUMP heap name="sga heap(4,3)" desc=0x6007d678

Total heap size = 67108776

HEAP DUMP heap name="sga heap(5,0)" desc=0x60082638

Total heap size = 67108776

HEAP DUMP heap name="sga heap(5,1)" desc=0x60083e90

Total heap size = 67108776

HEAP DUMP heap name="sga heap(5,2)" desc=0x600856e8

Total heap size = 67108776

HEAP DUMP heap name="sga heap(5,3)" desc=0x60086f40

Total heap size = 67108776

HEAP DUMP heap name="sga heap(6,0)" desc=0x6008bf00

Total heap size =134217552

HEAP DUMP heap name="sga heap(6,1)" desc=0x6008d758

Total heap size = 67108776

HEAP DUMP heap name="sga heap(6,2)" desc=0x6008efb0

Total heap size = 67108776

HEAP DUMP heap name="sga heap(6,3)" desc=0x60090808

Total heap size = 67108776

--//這樣可以看到每個子池有幾個子子池,並且每個的大小.

總結:

--//總之注意,如果手工管理記憶體,設定sga_target=0G的情況下,適當設定_kghdsidx_count,shared_pool_size,db_cache_size值.避免

--//shared pool latch僅僅1個的情況.

--//我個性喜歡手工管理記憶體設定sga_target=sga_max_size,設定shared_pool_size,db_cache_size基本不會轉換.

--//附上sgastatx.sql指令碼.

$ cat sgastatx.sql

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

--

-- File name: sgastatx

-- Purpose: Show shared pool stats by sub-pool from X$KSMSS

--

-- Author: Tanel Poder

-- Copyright: (c)

--

-- Usage: @sgastatx <statistic name>

-- @sgastatx "free memory"

-- @sgastatx cursor

--

-- Other: The other script for querying V$SGASTAT is called sgastat.sql

--

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

COL sgastatx_subpool HEAD SUBPOOL FOR a30

PROMPT

PROMPT -- All allocations:

SELECT

'shared pool ('||NVL(DECODE(TO_CHAR(ksmdsidx),'0','0 - Unused',ksmdsidx), 'Total')||'):' sgastatx_subpool

, SUM(ksmsslen) bytes

, ROUND(SUM(ksmsslen)/1048576,2) MB

FROM

x$ksmss

WHERE

ksmsslen > 0

--AND ksmdsidx > 0

GROUP BY ROLLUP

( ksmdsidx )

ORDER BY

sgastatx_subpool ASC

/

BREAK ON sgastatx_subpool SKIP 1

PROMPT -- Allocations matching "&1":

SELECT

subpool sgastatx_subpool

, name

, SUM(bytes)

, ROUND(SUM(bytes)/1048576,2) MB

FROM (

SELECT

'shared pool ('||DECODE(TO_CHAR(ksmdsidx),'0','0 - Unused',ksmdsidx)||'):' subpool

, ksmssnam name

, ksmsslen bytes

FROM

x$ksmss

WHERE

ksmsslen > 0

AND LOWER(ksmssnam) LIKE LOWER('%&1%')

)

GROUP BY

subpool

, name

ORDER BY

subpool ASC

, SUM(bytes) DESC

/

BREAK ON sgastatx_subpool DUP

[20190507]sga_target 的設定和ORA-04031錯誤2.txt