Latch problem.

Question

Hi All,
I've severe latching problem in my database, when I look in AWR but confused what is causing it.
Can someone guide me on this?
NoWait Waiter
Latch Name Where Misses Sleeps Sleeps
In memory undo latch ktiFlush: child 0 5 0
In memory undo latch kturbk 0 2 2
cache buffers chains kcbchg: kslbegin: bufs not 0 573 69
cache buffers chains kcbgtcr: fast path 0 380 554
cache buffers chains kcbgtcr: kslbegin excl 0 298 547
cache buffers chains kcbrls: kslbegin 0 183 153
cache buffers chains kcbzgb: scan from tail. no 0 83 0
cache buffers chains kcbibr 0 31 40
cache buffers chains kcbchg: kslbegin: call CR 0 10 70
cache buffers chains kcbgcur: kslbegin 0 4 13
cache buffers chains kcbget: pin buffer 0 3 72
cache buffers chains kcbnew: new latch again 0 3 18
cache buffers chains kcbzwb 0 2 3
cache buffers chains kcbbxsv 0 1 3
cache buffers chains kcbcge 0 1 5
cache buffers lru chain kcbzgws 0 45 0
cache buffers lru chain kcbibr 0 43 97
cache buffers lru chain kcbo_link_q 0 20 5
cache buffers lru chain kcbw_quiesce_granule 0 5 0
cache buffers lru chain kcbgtcr:CR Scan:KCBRSKIP 0 1 0
enqueues ksqdel 0 1 0
kks stats kks stats alloc/free 0 1 1
library cache kglobpn: child: 0 2,978 4,471
library cache kgldti: 2child 0 2,417 12
library cache kglLockCursor 0 1,604 3,398
library cache kglpin 0 1,426 538
library cache kglpndl: child: after proc 0 1,185 7
library cache kglhdgn: child: 0 766 1,485
library cache kglpnp: child 0 618 8,902
library cache kglhdgc: child: 0 331 0
library cache kgldte: child 0 0 95 809
library cache kglpndl: child: before pro 0 92 1,800
library cache kglic 0 50 0
library cache kglnti 0 30 0
library cache kglati 0 28 0
library cache kglobld 0 15 21
library cache kglScanDependency 0 7 2
library cache kglukp: child 0 6 5
library cache kglhdbrnl: child 0 1 0
library cache lock kgllkdl: child: no lock ha 0 10,017 217
library cache lock kgllkdl: child: cleanup 0 87 119
library cache lock kgllkal: child: multiinsta 0 80 48
library cache lock alloc kgllkget 0 1 1
library cache pin kglpndl 0 34 6
library cache pin kglpnp: child 0 17 23
library cache pin kglpnal: child: alloc spac 0 13 35
object queue header oper kcbo_switch_cq 0 12 5
object queue header oper kcbw_link_q 0 9 11
object queue header oper kcbo_link_q:reget 0 5 0
object queue header oper kcbw_unlink_q 0 2 10
redo allocation kcrfw_redo_gen: redo alloc 0 13 0
row cache objects kqreqd: reget 0 7 0
row cache objects kqreqd 0 1 0
session allocation ksuprc 0 44 7
session allocation ksudlc 0 24 25
session allocation ksuxds: not user session 0 16 1
session allocation ksucri 0 9 62
session allocation kspallmod 0 2 0
shared pool kghalo 0 2,269 126
shared pool kghupr1 0 690 3,122
Thanks for the help.
Thanks,
Rana.

Answer 1

DB Name         DB Id    Instance     Inst Num Release     RAC Host
orvprd        3135597156 orvprd              1 10.2.0.3.0  NO  ix205
              Snap Id      Snap Time      Sessions Curs/Sess
Begin Snap:      8273 22-Jun-09 03:00:39       132      22.4
  End Snap:      8275 22-Jun-09 05:00:42       135      19.3
   Elapsed:              120.05 (mins)
   DB Time:              565.08 (mins)
Cache Sizes
~~~~~~~~~~~                       Begin        End
               Buffer Cache:     7,392M     7,264M  Std Block Size:         8K
           Shared Pool Size:     2,768M     2,896M      Log Buffer:    14,340K
Load Profile
~~~~~~~~~~~~                            Per Second       Per Transaction
                  Redo size:             33,684.43              7,421.03
              Logical reads:            133,813.99             29,480.60
              Block changes:              4,946.72              1,089.81
             Physical reads:                  2.37                  0.52
            Physical writes:                 12.92                  2.85
                 User calls:                154.34                 34.00
                     Parses:                438.57                 96.62
                Hard parses:                  1.26                  0.28
                      Sorts:              5,130.10              1,130.21
                     Logons:                  0.07                  0.02
                   Executes:              5,604.35              1,234.70
               Transactions:                  4.54
  % Blocks changed per Read:    3.70    Recursive Call %:    98.52
Rollback per transaction %:    0.18       Rows per Sort:     2.85
Instance Efficiency Percentages (Target 100%)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            Buffer Nowait %:  100.00       Redo NoWait %:  100.00
            Buffer  Hit   %:  100.00    In-memory Sort %:  100.00
            Library Hit   %:  100.01        Soft Parse %:   99.71
         Execute to Parse %:   92.17         Latch Hit %:   99.32
Parse CPU to Parse Elapsd %:    8.09     % Non-Parse CPU:   99.46
Shared Pool Statistics        Begin    End
             Memory Usage %:   84.14   84.89
    % SQL with executions>1:   97.57   97.11
  % Memory for SQL w/exec>1:   95.66   95.31
Top 5 Timed Events                                         Avg %Total
~~~~~~~~~~~~~~~~~~                                        wait   Call
Event                                 Waits    Time (s)   (ms)   Time Wait Class
CPU time                                         14,995          44.2
TCP Socket (KGAS)                   611,193       6,230     10   18.4    Network
latch: library cache                 21,661       4,756    220   14.0 Concurrenc
latch: shared pool                    3,333         320     96    0.9 Concurrenc
db file sequential read              17,316         193     11    0.6   User I/O
          -------------------------------------------------------------