New Container Management capability in EM Express 12c release 2
The EM
express in 12.1.0.1 offers a lightweight
GUI for managing and administering the Oracle Database instance out of the box.
You could not, however, administer the containers of a CDB.
But in EM
Express 12.1.0.2, you can. It now allows
administration of the containers. There is a clickable link in the home page,
which takes the user to the containers page.
The
containers page looks like this. It is showing 2 container databases, PDB1 and
PDB2, and it is seen that PDB1 is down whereas PDB2 is running.
A couple
of useful administrative features are available. There is the ability to
create, drop, plug and unplug pluggable databases. These features will be very
useful to a dba.
You can
select a pluggable database from the grid and access its performance hub page,
as shown below. The performance hub allows monitoring the database performance,
generate/view performance reports, identify issues, and tune high load sql.
Another
interesting thing is that this CDB is using a resource plan, which can also be
administered from within the EM Express.
CDB
resource plans are two-tier plans.
The link
below describes how CDB resource plans work.
At the
first tier, which is at the CDB level, the administrator specifies, for each
PDB, the proportion of server resources (basically its CPU and parallel
servers) it will be allowed to use, by specifying a relative number (known as a
share). So if there are 2 PDBS with PDB1 getting 2 shares AND PDB2 4, then the
resources are shared in the 2:4 ratio.
A max
utilization cap can be specified, so that no Pdb ever uses up all the available
cpu or parallel query slaves. See screenshot for reference:
Further,
it is possible to establish a default plan directive at the CDB level which
will apply to newly created PDBs, for whom the directives are not explicitly
set at creation time, see above.
At the
second tier, which is now at the PDB level, resources can be allocated by using
the 11g style resource consumer groups, resource plan directives, etc.
In the
screen grab below (part of the Containers screen again) it is seen that the
pluggable database named PDB2 gets 3 shares. Its depicted graphically under the
column CPU Resource Limits
While the
pluggable database PDB1 gets only 2.
In this
case, both PDBs are allowed to use all the available cpu and all the available
parallel slaves, if they require them.
With the container
management capability in new 12.1.0.2 release, EM Express has undergone significant
improvements, which will be useful to a dba. He/she will now need to depend
less on the Cloud Control.
