AWR analysis [message #479104] |
Thu, 14 October 2010 10:21 |
dba1234
Messages: 1 Registered: October 2010
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Junior Member |
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DB Name DB Id Instance Inst num Startup Time Release RAC
2725233562 1 31-Aug-10 13:08 11.1.0.7.0 NO
Host Name Platform CPUs Cores Sockets Memory (GB)
sgpmv070 Linux x86 64-bit 2 1.84
Snap Id Snap Time Sessions Cursors/Session
Begin Snap: 4494 23-Sep-10 14:00:47 50 8.2
End Snap: 4495 23-Sep-10 15:00:01 51 8.2
Elapsed: 59.22 (mins)
DB Time: 123.48 (mins)
Cache Sizes
Begin End
Buffer Cache: 184M 184M Std Block Size: 16K
Shared Pool Size: 304M 304M Log Buffer: 6,504K
Load Profile
Per Second Per Transaction Per Exec Per Call
DB Time(s): 2.1 49.7 1.01 0.74
DB CPU(s): 1.7 39.6 0.80 0.59
Redo size: 757.7 18,068.5
Logical reads: 5,618.7 133,983.5
Block changes: 2.1 49.8
Physical reads: 2,992.6 71,361.3
Physical writes: 1,275.7 30,419.2
User calls: 2.8 67.0
Parses: 1.8 44.0
Hard parses: 0.0 0.3
W/A MB processed: 2,453,233.4 58,500,034.2
Logons: 0.0 0.7
Executes: 2.1 49.3
Rollbacks: 0.0 0.0
Transactions: 0.0
Instance Efficiency Percentages (Target 100%)
Buffer Nowait %: 100.00 Redo NoWait %: 100.00
Buffer Hit %: 99.82 In-memory Sort %: 85.62
Library Hit %: 99.06 Soft Parse %: 99.34
Execute to Parse %: 10.82 Latch Hit %: 100.00
Parse CPU to Parse Elapsd %: 0.00 % Non-Parse CPU: 99.99
Shared Pool Statistics
Begin End
Memory Usage %: 89.00 89.04
% SQL with executions>1: 89.61 89.59
% Memory for SQL w/exec>1: 85.55 84.35
Top 5 Timed Foreground Events
Event Waits Time(s) Avg wait (ms) % DB time Wait Class
DB CPU 5,893 79.54
direct path write temp 1,139,089 1,331 1 17.96 User I/O
direct path read temp 6,440,066 92 0 1.24 User I/O
direct path read 415,397 36 0 0.49 User I/O
db file sequential read 16,639 21 1 0.28 User I/O
Host CPU (CPUs: 2 Cores: Sockets: )
Load Average Begin Load Average End %User %System %WIO %Idle
2.50 2.17 80.6 3.5 12.2 15.2
Instance CPU
%Total CPU %Busy CPU %DB time waiting for CPU (Resource Manager)
82.9 97.7 0.0
Memory Statistics
Begin End
Host Mem (MB): 1,883.4 1,883.4
SGA use (MB): 520.0 520.0
PGA use (MB): 386.2 354.5
% Host Mem used for SGA+PGA: 48.12 48.12
Time Model Statistics
• Total time in database user-calls (DB Time): 7408.6s
• 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 7,251.80 97.88
DB CPU 5,892.52 79.54
PL/SQL execution elapsed time 10.81 0.15
parse time elapsed 7.17 0.10
hard parse elapsed time 5.54 0.07
Java execution elapsed time 2.77 0.04
hard parse (sharing criteria) elapsed time 1.88 0.03
connection management call elapsed time 1.01 0.01
failed parse elapsed time 0.00 0.00
repeated bind elapsed time 0.00 0.00
DB time 7,408.56
background elapsed time 33.94
background cpu time 1.35
1. Parse CPU to parse elapsed is 0%. This means that Oracle waits for resources during parsing of SQL statements. But my non parse CPU % is 99.99% and soft parse % 99.34. What is the impact of this parse CPU to parse elapsed being 0%?
2. execute to parse % is also too low? so which means parsing is done and not executing properly. what should be looked in for this?
3. My timed model statistics show sql execute elapsed time on the top with 97%. Can i conclude the SQL execution taking up almost all DB time and look for SQL under "SQL ordered by Elapsed Time"?
Can you please let me know what else should be looked into?
[Updated on: Thu, 14 October 2010 10:24] by Moderator Report message to a moderator
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Re: AWR analysis [message #479796 is a reply to message #479104] |
Tue, 19 October 2010 06:18 |
kamkan
Messages: 27 Registered: April 2007 Location: Chennai, INDIA
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Junior Member |
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Hi,
Look for the Top 5 Timed Foreground Events. Investigate what is triggering these events? (Ignore idle events)
SQL ordered by Elapsed Time => Always helps to find the time consuming sql (Observe the elapsed time as well as number of executions also).
SQL ordered by Reads should also be noticed for I/O intensive queries.
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