In your multitenant container database (CDB) containing pluggable databases (PDB), users
complain about performance degradation.
How does real-time Automatic database Diagnostic Monitor (ADDM) check performance
degradation and provide solutions?
A.
It collects data from SGA and compares it with a preserved snapshot.
B.
It collects data from SGA, analyzes it, and provides a report.
C.
It collects data from SGA and compares it with the latest snapshot.
D.
It collects data from both SGA and PGA, analyzes it, and provides a report.
Explanation:
Note:
* The multitenant architecture enables an Oracle database to function as a multitenant container
database (CDB) that includes zero, one, or many customer-created pluggable databases (PDBs).
A PDB is a portable collection of schemas, schema objects, and nonschema objects that appears
to an Oracle Net client as a non-CDB. All Oracle databases before Oracle Database 12c were
non-CDBs.
* The System Global Area (SGA) is a group of shared memory areas that are dedicated to an
Oracle “instance” (an instance is your database programs and RAM).
* The PGA (Program or Process Global Area) is a memory area (RAM) that stores data and
control information for a single process.
Also not agree!
An ADDM analysis can be performed on a pair of AWR snapshots and a set of instances from the same database. The pair of AWR snapshots define the time period for analysis, and the set of instances define the target for analysis.
An ADDM analysis is performed each time an AWR snapshot is taken and the results are saved in the database. The time period analyzed by ADDM is defined by the last two snapshots (the last hour by default).
Me for C! Any idea?
The answer is right. Real-Time ADDM does not access the AWR snapshots, but ASH recent activity from SGA data.
Agree. Real-Time ADDM access ASH recent activity from SGA.
Thnx, Shawn! Its about Real-Time, ok.
pls check other questions 😉
You actually make it seem so easy with your presentation but I find this matter to be really something which I think I would never understand. It seems too complicated and extremely broad for me. I am looking forward for your next post, I’ll try to get the hang of it!
C
Bot C it is B
B.
It collects data from SGA, analyzes it, and provides a report.
B – OK in this mode ADDM noot analyze snapshot only 10 min read direcli from SGA dont generate any snapshot to analize !!
B
B
B.
Real time ADDM – reads last 10 minutes data from SGA/Active Session Hisotry pool.
B
Only B is correct. real-time ADDM collects from SGA ,analyze and generate report.
Oracle Database 12c: new Features for Administrator 15-10 Volume II Edition 2.0:
If you do not want to shut down the database instance right away, perform Real-Time ADDM deeper analysis. It will collect data from SGA, perform an analysis to provide you with a report of the root causes of the situation with recommendations and possible actions.