Hi Experts,
I am trying to understand the AWR report and its various sections (step-by-step). This will help in better (advanced) understanding of the performance issues, if any, with the the database.
Currently, reading this wonderful article by Frank Pachot. (He might also join soon )
My database parameters:
| DB Name | DB Id | Instance | Inst num | Startup Time | Release | RAC |
|---|
| aaa | 1234 | bbb | 1 | 13-Mar-14 02:03 | 11.2.0.3.0 | NO |
| Host Name | Platform | CPUs | Cores | Sockets | Memory (GB) |
|---|
| cccdd | Solaris[tm] OE (64-bit) | 54 | 27 | 7 | 512.00 |
Top 5 Timed Foreground Events:
| Event | Waits | Time(s) | Avg wait (ms) | % DB time | Wait Class |
|---|
| resmgr:cpu quantum | 37,736,105 | 1,045,145 | 28 | 60.41 | Scheduler |
| DB CPU | | 271,637 | | 15.70 | |
| db file sequential read | 29,240,661 | 149,467 | 5 | 8.64 | User I/O |
| enq: TX - row lock contention | 374 | 87,043 | 232734 | 5.03 | Application |
| read by other session | 1,384,444 | 37,584 | 27 | 2.17 | User I/O |
Doubts:
1) The first event "resmgr:cpu quantum" seems to be the scheduler. It is at the top. Is that a normal scenario?
2) The fourth event "enq: TX - row lock contention" has the maximum "Avg Wait". Is it due to some query and are will other processes get affected by this lock?
Also reading this interesting link - DB CPU on top 5 Timed Foreground Events in AWR Report, AWR Report, DB CPU, Oracle Database tuning
Just want to understand these various things.
Please advise and share your thoughts. Will be a good learning experience for all newbies.
Thanks and Regards,
-- Ranit
( on Oracle 11.2.0.3.0 - Exadata )