Hi All,
we are having a severe performance issue in my database when we are running batch jobs.
This was a new database(11.2.0.2) and we are testing the performance by running some batch jobs. These batch jobs included some inserts and updates.
I am seeing read by other session in top 5 timed events and cache buffers chains in Latch Miss Sources section.
Please help me to solve this out.
Inst Num Startup Time Release RAC
------------ ----------- ------------ -------- --------------- ----------- ---
1 27-Feb-12 09:03 11.2.0.2.0 NO
Platform CPUs Cores Sockets Memory(GB)
--------------------------- ---- ----- ------- ----------
Linux x86 64-bit 8 8 8 48.00
Snap Id Snap Time Sessions Curs/Sess
--------- ------------------- -------- ---------
Begin Snap: 5605 29-Feb-12 03:00:27 63 4.5
End Snap: 5614 29-Feb-12 12:00:47 63 4.3
Elapsed: 540.32 (mins)
DB Time: 1,774.23 (mins)
Cache Sizes Begin End
~~~~~~~~~~~ ---------- ----------
Buffer Cache: 1,952M 1,952M Std Block Size: 16K
Shared Pool Size: 1,024M 1,024M Log Buffer: 18,868K
Load Profile Per Second Per Transaction Per Exec Per Call
~~~~~~~~~~~~ --------------- --------------- ---------- ----------
DB Time(s): 3.3 0.8 0.02 0.05
DB CPU(s): 1.1 0.3 0.01 0.02
Redo size: 55,763.8 13,849.3
Logical reads: 23,906.6 5,937.4
Block changes: 325.7 80.9
Physical reads: 665.6 165.3
Physical writes: 40.4 10.0
User calls: 60.7 15.1
Parses: 10.6 2.6
Hard parses: 1.1 0.3
W/A MB processed: 0.6 0.2
Logons: 0.1 0.0
Executes: 151.2 37.6
Rollbacks: 0.0 0.0
Transactions: 4.0
Instance Efficiency Percentages (Target 100%)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Buffer Nowait %: 99.94 Redo NoWait %: 100.00
Buffer Hit %: 97.90 In-memory Sort %: 100.00
Library Hit %: 98.06 Soft Parse %: 90.16
Execute to Parse %: 92.96 Latch Hit %: 100.00
Parse CPU to Parse Elapsd %: 76.71 % Non-Parse CPU: 98.57
Shared Pool Statistics Begin End
------ ------
Memory Usage %: 89.38 87.96
% SQL with executions>1: 97.14 95.15
% Memory for SQL w/exec>1: 96.05 92.46
Top 5 Timed Foreground Events
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Avg
wait % DB
Event Waits Time(s) (ms) time Wait Class
------------------------------ ------------ ----------- ------ ------ ----------
db file sequential read 14,092,706 65,613 5 61.6 User I/O
DB CPU 34,819 32.7
read by other session 308,534 1,260 4 1.2 User I/O
direct path read 97,454 987 10 .9 User I/O
db file scattered read 71,870 910 13 .9 User I/O
Host CPU (CPUs: 8 Cores: 8 Sockets: 8)
~~~~~~~~ Load Average
Begin End %User %System %WIO %Idle
--------- --------- --------- --------- --------- ---------
0.43 0.36 13.7 0.6 9.7 85.7
Instance CPU
~~~~~~~~~~~~
% of total CPU for Instance: 13.5
% of busy CPU for Instance: 94.2
%DB time waiting for CPU - Resource Mgr: 0.0
Memory Statistics
~~~~~~~~~~~~~~~~~ Begin End
Host Mem (MB): 49,152.0 49,152.0
SGA use (MB): 3,072.0 3,072.0
PGA use (MB): 506.5 629.1
% Host Mem used for SGA+PGA: 7.28 7.53
Time Model Statistics
-> Total time in database user-calls (DB Time): 106453.8s
-> Statistics including the word "background" measure background process
time, and so do not contribute to the DB time statistic
-> Ordered by % or DB time desc, Statistic name
Statistic Name Time (s) % of DB Time
------------------------------------------ ------------------ ------------
sql execute elapsed time 105,531.1 99.1
DB CPU 34,818.8 32.7
parse time elapsed 714.7 .7
hard parse elapsed time 684.8 .6
PL/SQL execution elapsed time 161.9 .2
PL/SQL compilation elapsed time 44.2 .0
connection management call elapsed time 16.9 .0
hard parse (sharing criteria) elapsed time 10.2 .0
hard parse (bind mismatch) elapsed time 9.4 .0
sequence load elapsed time 2.9 .0
repeated bind elapsed time 0.5 .0
failed parse elapsed time 0.0 .0
DB time 106,453.8
background elapsed time 1,753.9
background cpu time 61.7
-------------------------------------------------------------
Operating System Statistics
-> *TIME statistic values are diffed.
All others display actual values. End Value is displayed if different
-> ordered by statistic type (CPU Use, Virtual Memory, Hardware Config), Name
Statistic Value End Value
------------------------- ---------------------- ----------------
BUSY_TIME 3,704,415
IDLE_TIME 22,203,740
IOWAIT_TIME 2,517,864
NICE_TIME 3
SYS_TIME 145,696
USER_TIME 3,557,758
LOAD 0 0
RSRC_MGR_CPU_WAIT_TIME 0
VM_IN_BYTES 358,813,045,760
VM_OUT_BYTES 29,514,830,848
PHYSICAL_MEMORY_BYTES 51,539,607,552
NUM_CPUS 8
NUM_CPU_CORES 8
NUM_CPU_SOCKETS 8
GLOBAL_RECEIVE_SIZE_MAX 4,194,304
GLOBAL_SEND_SIZE_MAX 1,048,586
TCP_RECEIVE_SIZE_DEFAULT 87,380
TCP_RECEIVE_SIZE_MAX 4,194,304
TCP_RECEIVE_SIZE_MIN 4,096
TCP_SEND_SIZE_DEFAULT 16,384
TCP_SEND_SIZE_MAX 4,194,304
TCP_SEND_SIZE_MIN 4,096
-------------------------------------------------------------
Operating System Statistics -
Snap Time Load %busy %user %sys %idle %iowait
--------------- -------- -------- -------- -------- -------- --------
29-Feb 03:00:27 0.4 N/A N/A N/A N/A N/A
29-Feb 04:00:35 1.4 11.9 11.2 0.6 88.1 14.3
29-Feb 05:00:41 1.7 13.8 13.2 0.6 86.2 15.8
29-Feb 06:00:48 1.5 14.0 13.5 0.6 86.0 12.3
29-Feb 07:01:00 1.8 16.3 15.8 0.5 83.7 10.4
29-Feb 08:00:12 2.6 23.2 22.5 0.6 76.8 12.6
29-Feb 09:00:26 1.3 16.6 16.0 0.5 83.4 5.7
29-Feb 10:00:33 1.2 13.8 13.3 0.5 86.2 2.0
29-Feb 11:00:43 1.3 14.5 14.0 0.5 85.5 3.8
29-Feb 12:00:47 0.4 4.9 4.2 0.7 95.1 10.6
-------------------------------------------------------------
Foreground Wait Class
-> s - second, ms - millisecond - 1000th of a second
-> ordered by wait time desc, waits desc
-> %Timeouts: value of 0 indicates value was < .5%. Value of null is truly 0
-> Captured Time accounts for 97.9% of Total DB time 106,453.79 (s)
-> Total FG Wait Time: 69,415.64 (s) DB CPU time: 34,818.79 (s)
Avg
%Time Total Wait wait
Wait Class Waits -outs Time (s) (ms) %DB time
-------------------- ---------------- ----- ---------------- -------- ---------
User I/O 14,693,843 0 69,222 5 65.0
DB CPU 34,819 32.7
Commit 40,629 0 119 3 0.1
System I/O 26,504 0 57 2 0.1
Network 1,945,010 0 11 0 0.0
Other 125,200 99 4 0 0.0
Application 2,673 0 2 1 0.0
Concurrency 3,059 0 1 0 0.0
Configuration 31 19 0 15 0.0
-------------------------------------------------------------
Foreground Wait Events
-> s - second, ms - millisecond - 1000th of a second
-> Only events with Total Wait Time (s) >= .001 are shown
-> ordered by wait time desc, waits desc (idle events last)
-> %Timeouts: value of 0 indicates value was < .5%. Value of null is truly 0
Avg
%Time Total Wait wait Waits % DB
Event Waits -outs Time (s) (ms) /txn time
-------------------------- ------------ ----- ---------- ------- -------- ------
db file sequential read 14,092,706 0 65,613 5 108.0 61.6
read by other session 308,534 0 1,260 4 2.4 1.2
direct path read 97,454 0 987 10 0.7 .9
db file scattered read 71,870 0 910 13 0.6 .9
db file parallel read 35,001 0 372 11 0.3 .3
log file sync 40,629 0 119 3 0.3 .1
control file sequential re 26,504 0 57 2 0.2 .1
direct path read temp 14,499 0 49 3 0.1 .0
direct path write temp 9,186 0 28 3 0.1 .0
SQL*Net message to client 1,923,973 0 5 0 14.7 .0
SQL*Net message from dblin 1,056 0 5 5 0.0 .0
Disk file operations I/O 8,848 0 2 0 0.1 .0
ASM file metadata operatio 36 0 2 54 0.0 .0
SQL*Net break/reset to cli 2,636 0 1 1 0.0 .0
ADR block file read 472 0 1 1 0.0 .0
os thread startup 8 0 1 74 0.0 .0
SQL*Net more data to clien 17,656 0 1 0 0.1 .0
asynch descriptor resize 123,852 100 0 0 0.9 .0
local write wait 110 0 0 4 0.0 .0
utl_file I/O 55,635 0 0 0 0.4 .0
log file switch (private s 8 0 0 52 0.0 .0
cursor: pin S wait on X 2 0 0 142 0.0 .0
enq: KO - fast object chec 13 0 0 20 0.0 .0
PX Deq: Slave Session Stat 248 0 0 1 0.0 .0
enq: RO - fast object reus 18 0 0 11 0.0 .0
latch: cache buffers chain 2,511 0 0 0 0.0 .0
latch: shared pool 195 0 0 1 0.0 .0
CSS initialization 12 0 0 8 0.0 .0
PX qref latch 54 100 0 2 0.0 .0
SQL*Net more data from cli 995 0 0 0 0.0 .0
SQL*Net more data from dbl 300 0 0 0 0.0 .0
kksfbc child completion 1 100 0 56 0.0 .0
library cache: mutex X 244 0 0 0 0.0 .0
PX Deq: Signal ACK RSG 124 0 0 0 0.0 .0
undo segment extension 6 100 0 7 0.0 .0
PX Deq: Signal ACK EXT 124 0 0 0 0.0 .0
library cache load lock 3 0 0 9 0.0 .0
ADR block file write 45 0 0 1 0.0 .0
CSS operation: action 12 0 0 2 0.0 .0
reliable message 28 0 0 1 0.0 .0
CSS operation: query 72 0 0 0 0.0 .0
latch: row cache objects 14 0 0 1 0.0 .0
enq: SQ - contention 17 0 0 0 0.0 .0
latch free 32 0 0 0 0.0 .0
buffer busy waits 52 0 0 0 0.0 .0
enq: PS - contention 16 0 0 0 0.0 .0
enq: TX - row lock content 6 0 0 1 0.0 .0
SQL*Net message to dblink 1,018 0 0 0 0.0 .0
cursor: pin S 23 0 0 0 0.0 .0
latch: cache buffers lru c 8 0 0 0 0.0 .0
SQL*Net message from clien 1,923,970 0 944,508 491 14.7
jobq slave wait 66,732 100 33,334 500 0.5
Streams AQ: waiting for me 6,481 100 32,412 5001 0.0
wait for unread message on 32,858 98 32,411 986 0.3
PX Deq: Execution Msg 1,448 0 190 131 0.0
PX Deq: Execute Reply 1,196 0 74 62 0.0
HS message to agent 228 0 4 19 0.0
single-task message 42 0 4 97 0.0
PX Deq Credit: send blkd 904 0 2 3 0.0
PX Deq Credit: need buffer 205 0 1 3 0.0
Foreground Wait Events
-> s - second, ms - millisecond - 1000th of a second
-> Only events with Total Wait Time (s) >= .001 are shown
-> ordered by wait time desc, waits desc (idle events last)
-> %Timeouts: value of 0 indicates value was < .5%. Value of null is truly 0
Avg
%Time Total Wait wait Waits % DB
Event Waits -outs Time (s) (ms) /txn time
-------------------------- ------------ ----- ---------- ------- -------- ------
PX Deq: Table Q Normal 4,291 0 1 0 0.0
PX Deq: Join ACK 124 0 0 1 0.0
PX Deq: Parse Reply 124 0 0 0 0.0
KSV master wait 256 0 0 0 0.0
Latch Miss Sources
-> only latches with sleeps are shown
-> ordered by name, sleeps desc
NoWait Waiter
Latch Name Where Misses Sleeps Sleeps
------------------------ -------------------------- ------- ---------- --------
ASM map operation freeli kffmTranslate2 0 2 0
DML lock allocation ktadmc 0 2 0
FOB s.o list latch ksfd_allfob 0 2 2
In memory undo latch ktiFlushMe 0 5 0
In memory undo latch ktichg: child 0 3 0
PC and Classifier lists No latch 0 6 0
Real-time plan statistic keswxAddNewPlanEntry 0 20 20
SQL memory manager worka qesmmIRegisterWorkArea:1 0 1 1
active service list kswslogon: session logout 0 23 12
active service list kswssetsvc: PX session swi 0 6 1
active service list kswsite: service iterator 0 1 0
archive process latch kcrrgpll 0 3 3
cache buffers chains kcbgtcr_2 0 1,746 573
cache buffers chains kcbgtcr: fast path (cr pin 0 1,024 2,126
cache buffers chains kcbgcur_2 0 60 8
cache buffers chains kcbchg1: kslbegin: bufs no 0 16 3
cache buffers chains kcbgtcr: fast path 0 14 20
cache buffers chains kcbzibmlt: multi-block rea 0 10 0
cache buffers chains kcbrls_2 0 9 53
cache buffers chains kcbgtcr: kslbegin shared 0 8 1
cache buffers chains kcbrls_1 0 7 84
cache buffers chains kcbgtcr: kslbegin excl 0 6 14
cache buffers chains kcbnew: new latch again 0 6 0
cache buffers chains kcbzgb: scan from tail. no 0 6 0
cache buffers chains kcbzwb 0 5 8
cache buffers chains kcbgcur: fast path (shr) 0 3 0
cache buffers chains kcbget: pin buffer 0 3 0
cache buffers chains kcbzhngcbk2_1 0 1 0
cache buffers lru chain kcbzgws 0 19 0
cache buffers lru chain kcbo_link_q 0 3 0
call allocation ksuxds 0 14 10
call allocation ksudlp: top call 0 2 3
enqueue hash chains ksqgtl3 0 2 1
enqueue hash chains ksqrcl 0 1 2
enqueues ksqgel: create enqueue 0 1 0
object queue header oper kcbo_unlink_q 0 5 2
object queue header oper kcbo_sw_buf 0 2 0
object queue header oper kcbo_link_q 0 1 2
object queue header oper kcbo_switch_cq 0 1 2
object queue header oper kcbo_switch_mq_bg 0 1 4
parallel query alloc buf kxfpbalo 0 1 1
process allocation ksucrp:1 0 2 0
process queue reference kxfpqrsnd 0 1 0
qmn task queue latch kwqmnmvtsks: delay to read 0 1 0
redo allocation kcrfw_redo_gen: redo alloc 0 17 0
row cache objects kqreqd: reget 0 6 0
row cache objects kqrpre: find obj 0 6 13
row cache objects kqrso 0 2 0
row cache objects kqreqd 0 1 2
row cache objects kqrpre: init complete 0 1 1
shared pool kghalo 0 199 106
shared pool kghupr1 0 39 109
shared pool kghfre 0 18 19
shared pool kghalp 0 7 29
space background task la ktsj_grab_task 0 21 27
-------------------------------------------------------------
Mutex Sleep Summary
-> ordered by number of sleeps desc
Wait
Mutex Type Location Sleeps Time (ms)
--------------------- -------------------------------- ------------ ------------
Library Cache kglhdgn2 106 338 12
Library Cache kgllkc1 57 259 10
Library Cache kgllkdl1 85 123 21
Cursor Pin kkslce [KKSCHLPIN2] 70 286
Library Cache kglget2 2 31 1
Library Cache kglhdgn1 62 31 2
Library Cache kglpin1 4 26 1
Library Cache kglpnal1 90 18 0
Library Cache kglpndl1 95 15 2
Library Cache kgllldl2 112 6 0
Library Cache kglini1 32 1 0
-------------------------------------------------------------
Thanks in advance.