Best Practices for OMEGAMON XE for CICS "Enhanced 3270UI Near Term History" definitions and guidelines
Bob_Horne 1100008GYP Visits (8849)
In this blog we will discuss the best practices for configuring Near Term History (NTH) data collection for the OMEGAMON XE for CICS product. The information provided in this blog is applicable for both the OMEGAMON XE for CICS product component and the OMEGAMON XE for CICS TG product component.
The enhanced 3270UI Near Term History feature only requires that history collection be enabled for the desired attribute groups. The NTH reports viewed in the enhanced 3270UI are generated from the same history data that is used for the short-term history reports viewed in the Tivoli Enterprise Portal (TEP). This is also the same history data that might be exported to the Tivoli Data Warehouse by the Warehouse Proxy agent.
There is no limit on the range of Near Term History which can be displayed in the enhanced 3270UI. The amount of Near Term History data available for viewing in the enhanced 3270UI is limited only by size of the OMEGAMON Persistent Data Store (PDS). This is different than the viewing of short-term history on the TEP which is limited to the value set in the TEP KFW_REPORT_TERM_ BREAK_POINT environment variable which has a default value of 24 hours.
Where should Near Term History Collection be configured?
Users who have never previously configured history collection will likely choose to configure history collection via the enhanced 3270UI. This is the best approach to configure history collection for display in the enhanced 3270UI unless there is a specific need to configure history collection in the TEP.
If history collection was previously configured through the TEP interface, there is no requirement to make any changes to the history configuration to support the Near Term History feature of the enhanced 3270UI. The enhanced 3270UI history configuration facility will recognize and display any history configuration settings previously defined via the TEP interface.
There are only a few circumstances when a system administrator would need to configure history collection in the TEP rather than the enhanced 3270UI. One instance would be if there is a need to configure the Tivoli Data Warehouse (TDW) related settings. Another would be if there is a requirement to specify history collection at the TEMS.
History Configuration in the enhanced 3270UI
Option #5 under the View item in the enhanced 3270UI can be used to display the PDS Historical Collection control panel. On the PDS Historical Collection control panel a user can select the application for which history will be configured.
Below is a screen shot of the PDS Historical Collection control panel showing the various applications for which history can be configured in the given installation (see example below):
Selecting an application on the PDS Historical Collection control panel will display the Historical Tables panel. Listed on the Historical Tables panel are the attribute groups for which history can be configured.
Below is a screen shot of the Historical Tables panel for the OMEGAMON XE for CICS application component:
Only the attribute groups for which Near Term History is supported in the enhanced 3270UI will be displayed on the Historical Tables panel. The attribute groups that are displayed were selected for display in the enhanced 3270UI because they will provide the most useful history and they will not result in the costly collection of excessive numbers of rows of data per query.
On the Historical Tables panel the current status of history collection will be shown for each table. Selecting an attribute group will allow a system administrator to view, create, modify, or delete a history collection.
The screen example shown below shows the selection options available to a system administrator:
The Historical Tables panel will also display the status of CICSplex Task History and the CICSplex Application Trace. Selecting either the CICSplex Task History or the CICSplex Application Trace will display the status of the OMEGAMON Task History (ONDV) and the OMEGAMON Application Trace for each monitored CICS region.
Selecting Attribute Groups for history collection
When configuring history collection for the various attribute groups, a system administrator should give careful consideration to which attribute groups should be enabled for history collection. Note that additional system resources will be consumed during the history collection process and additional storage will be utilized in the PDS files for each additional attribute group configured. History collection should only be specified for those attribute groups where there is an anticipated need to view history. In addition a system administrator should never define multiple collection settings for the same attribute group.
Selecting a history collection time interval
Consideration needs to be given to the collection interval specified for each attribute group. A small interval will result in more frequent history collection. More frequent history collection will result in increased system overhead and more rows of history data in the PDS files.
It is also a good practice to make the collection interval consistent for the various attribute groups. This will help to insure that when navigating from panel to panel in enhanced 3270UI history mode the expected history data will have been collected for display.
Additional considerations for the OMEGAMON XE for CICS TG component
Internal data collection for a number of the OMEGAMON XE for CICSTG attribute groups is on a current minute sample basis rather than an accumulated history interval basis. For example, if you specify a history collection interval of five minutes for the attribute group, only the activity for the current minute will be collected. The internal data collectors are reset for each internal collection and the activity during the previous four one-minute intervals is not accumulated across the five minute interval.
If a system administrator has the need to insure that activity across all intervals is captured, then the system administrator should consider setting the history collection interval for the CICS TG attribute group to a one-minute interval. However, setting the history collection interval to a shorter time interval should only be done after having given careful consideration to the additional system overhead and DASD space associated with more frequent history collection intervals.
The capabilities described above are available with the OMEGAMON Performance Management Suite.