Hi, we are doing some performance testing, below is the extract from Statspack report. I see (RMAN backup & recovery I/O )"system io" as top wait event, but not sure which section of Statspack to look for. Please let me know if this is okay or what we need to check. thanks.
------------------------Statspack report starts-----------------------------
Database DB Id Instance Inst Num Startup Time Release RAC
~~~~~~~~ ----------- ------------ -------- --------------- ----------- ---
1267892134 PROD 1 06-Aug-16 20:46 11.2.0.4.0 NO
Host Name Platform CPUs Cores Sockets Memory (G)
~~~~ ---------------- ---------------------- ----- ----- ------- ------------
hostname Linux x86 64-bit 24 12 2 94.4
Snapshot Snap Id Snap Time Sessions Curs/Sess Comment
~~~~~~~~ ---------- ------------------ -------- --------- ------------------
Begin Snap: 407 03-Nov-16 20:08:16 86 13.9
End Snap: 408 03-Nov-16 21:08:18 94 13.6
Elapsed: 60.03 (mins) Av Act Sess: 0.5
DB time: 28.58 (mins) DB CPU: 28.72 (mins)
Cache Sizes Begin End
~~~~~~~~~~~ ---------- ----------
Buffer Cache: 6,848M Std Block Size: 8K
Shared Pool: 8,064M Log Buffer: 18,456K
Load Profile Per Second Per Transaction Per Exec Per Call
~~~~~~~~~~~~ ------------------ ----------------- ----------- -----------
DB time(s): 0.5 0.1 0.00 0.00
DB CPU(s): 0.5 0.1 0.00 0.00
Redo size: 33,082.6 7,156.5
Logical reads: 93,992.7 20,332.8
Block changes: 142.1 30.7
Physical reads: 1.0 0.2
Physical writes: 6.5 1.4
User calls: 141.1 30.5
Parses: 43.1 9.3
Hard parses: 0.4 0.1
W/A MB processed: 1.5 0.3
Logons: 1.5 0.3
Executes: 3,239.6 700.8
Rollbacks: 0.1 0.0
Transactions: 4.6
Instance Efficiency Indicators
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Buffer Nowait %: 100.00 Redo NoWait %: 100.00
Buffer Hit %: 100.00 Optimal W/A Exec %: 100.00
Library Hit %: 99.95 Soft Parse %: 99.09
Execute to Parse %: 98.67 Latch Hit %: 100.00
Parse CPU to Parse Elapsd %: 68.94 % Non-Parse CPU: 98.88
Shared Pool Statistics Begin End
------ ------
Memory Usage %: 82.93 83.20
% SQL with executions>1: 56.42 57.11
% Memory for SQL w/exec>1: 78.99 78.89
Top 5 Timed Events Avg %Total
~~~~~~~~~~~~~~~~~~ wait Call
Event Waits Time (s) (ms) Time
----------------------------------------- ------------ ----------- ------ ------
RMAN backup & recovery I/O 161,484 1,557 10 41.3
CPU time 1,502 39.9
Backup: MML create a backup piece 9 313 34829 8.3
Backup: MML write backup piece 7,056 150 21 4.0
Backup: MML commit backup piece 7 93 13329 2.5
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