Oracle Resource Usage Test
This test monitors how effectively the Oracle database server utilizes the session and process resources it is configured with. If the maximum limit to which the resource allocation can grow is violated, it is bound to deteriorate the performance of the server, as the server might not have the bandwidth to handle the additional sessions/processes.
This test is disabled by default. To enable the test, go to the enable / disable tests page using the menu sequence : Agents -> Tests -> Enable/Disable, pick Oracle Database as the Component type, Performance as the Test type, choose this test from the disabled tests list, and click on the << button to move the test to the ENABLED TESTS list. Finally, click the Update button.
Target of the test : An Oracle server (9i and 10g)
Agent deploying the test : An internal agent
Outputs of the test : One set of results for the session and process resources allocated to the Oracle server being monitored
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Measurement | Description | Measurement Unit | Interpretation |
---|---|---|---|
Initial allocation: |
Indicates the number of sessions/processes allocated at the time of creating the Oracle database instance. |
Number |
|
Current utilization : |
This measure indicates the number of sessions/processes currently active on the Oracle database server. |
Number |
If the value of the Current utilization measure exceeds the value of the Initial allocation measure, the additional required resources are allocated from the shared pool, where they must compete for space with other resources. During SGA reservation/initialization, a place is reserved in SGA for the INITIAL_ALLOCATION of resources. Based on usage, this allocation can later be changed using the SESSIONS and PROCESSES parameters in the init database parameter file. The Configured limit measure of this test reports this new configuration only. For most resources, the INITIAL_ALLOCATION value and the Configured limit will be the same. However, if the resource allocation is to be changed later, it is good practice to check the maximum utilization limit that Oracle prescribes for the database, and then make the change. This limit signifies the maximum number of sessions and processes the database can handle, given its current memory capacity. The Maximum utilization limit measure reports this Oracle-recommended value. If the value of the Current utilization measure, exceeds the Maximum utilization limit, then the performance of your database is bound to deteriorate. Therefore, ensure that the Config_Limit is always well within the Maximum utilization limit |
Maximum utilization limit: |
This measure indicates the maximum number of sessions/resources that can be allowed to run on the Oracle database server.
|
Number |
If you want to allocate more sessions/processes to your database than what is recommended by Oracle, then its best that you enhance the memory capacity of your database, before altering the resource configurations. |
Configured limit: |
This measure indicates the number of sessions/processes the Oracle server is currently configured to handle. |
Number |
|
Percentage utilized: |
Indicates the percentage of the configured number of sessions/processes (i.e., the Configured limit) that are currently utilized by the Oracle database instance. |
Percent |
Ideally, the value of this measure should be low. If this measure shows high value, then DBA should increase the configuration value of the SESSIONS & PROCESSES parameter in the database parameter file. Otherwise, DBA should identify idle sessions and terminate them, so as to make more space available for new sessions/processes. |