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Performance problem while CPU is 80% Idel ?

YoavJan 22 2013 — edited Jan 23 2013
Hi,

My end users are claim for performance problem during execution of batch process.
As you can see there are 1,745 statement executing each second.

Awr report shows 98.1% of the time , waits on CPU .
Also Awr report shows that Host CPU is :79.9% Idel.
The second wait event shows only 212 seconds waits on db file sequential read.
Yet , 4 minute in 1 hour period is seems not an issue.

Please advise
 

DB Name         DB Id    Instance     Inst Num Startup Time    Release     RAC 
------------ ----------- ------------ -------- --------------- ----------- --- 
QERP          xxx        erp                 1 21-Jan-13 15:40 11.2.0.2.0 ; NO 

Host Name        Platform                         CPUs Cores Sockets Memory(GB) 
---------------- -------------------------------- ---- ----- ------- ---------- 
erptst           HP-UX IA (64-bit)                  16    16       4     127.83 

              Snap Id      Snap Time      Sessions Curs/Sess 
            --------- ------------------- -------- --------- 
Begin Snap:     40066 22-Jan-13 20:00:52       207       9.6 
  End Snap:     40067 22-Jan-13 21:00:05       210       9.6 
   Elapsed:               59.21 (mins) 
   DB Time:              189.24 (mins) 

Cache Sizes                       Begin        End 
~~~~~~~~~~~                  ---------- ---------- 
               Buffer Cache:     8,800M     8,800M  Std Block Size:         8K 
           Shared Pool Size:     1,056M     1,056M      Log Buffer:    49,344K 

Load Profile              Per Second    Per Transaction   Per Exec   Per Call 
~~~~~~~~~~~~         ---------------    --------------- ---------- ---------- 
      DB Time(s):                3.2 ;               0.1 ;      0.00 ;      0.05 
       DB CPU(s):                3.1 ;               0.1 ;      0.00 ;      0.05 
       Redo size:          604,285.1 ;          27,271.3 
   Logical reads:          364,792.3 ;          16,463.0 
   Block changes:            3,629.5 ;             163.8 
  Physical reads:               21.5 ;               1.0 
Physical writes:               95.3 ;               4.3 
      User calls:               68.7 ;               3.1 
          Parses:              212.9 ;               9.6 
     Hard parses:                0.3 ;               0.0 
W/A MB processed:                1.2 ;               0.1 
          Logons:                0.3 ;               0.0 
        Executes:            1,745.2 ;              78.8 
       Rollbacks:                1.2 ;               0.1 
    Transactions:               22.2 

Instance Efficiency Percentages (Target 100%) 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
            Buffer Nowait %:  100.00 ;      Redo NoWait %:  100.00 
            Buffer  Hit   %:   99.99 ;   In-memory Sort %:  100.00 
            Library Hit   %:   99.95 ;       Soft Parse %:   99.85 
         Execute to Parse %:   87.80 ;        Latch Hit %:   99.99 
Parse CPU to Parse Elapsd %:   74.76 ;    % Non-Parse CPU:   99.89 

Shared Pool Statistics        Begin    End 
                              ------  ------ 
             Memory Usage %:   75.37 ;  76.85 
    % SQL with executions>1:   95.31 ;  85.98 
  % Memory for SQL w/exec>1:   90.33 ;  82.84 

Top 5 Timed Foreground Events 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
                                                           Avg 
                                                          wait   % DB 
Event                                 Waits     Time(s)   (ms)   time Wait Class 
------------------------------ ------------ ----------- ------ ------ ---------- 
DB CPU                                           11,144          98.1 
db file sequential read              52,714         214      4    1.9 User I/O 
SQL*Net break/reset to client        29,050           6      0     .1 Applicatio 
log file sync                         2,536           6      2     .0 Commit 
buffer busy waits                     4,338           2      1     .0 Concurrenc 
Host CPU (CPUs:   16 Cores:   16 Sockets:    4) 
~~~~~~~~         Load Average 
               Begin       End     %User   %System      %WIO     %Idle 
           --------- --------- --------- --------- --------- --------- 
                0.34 ;     0.33 ;     19.7 ;      0.4 ;      1.8 ;     79.9 
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Locked on Feb 20 2013
Added on Jan 22 2013
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