Reducing the number of duplicate impacts on an asset

This is a configurable impact analysis improvement. Previous “versions” of WebSphere Studio Asset Analyzer have always recorded multiple incoming impacts on impacted assets where the “source” of the impact differs. This means that there might be multiple paths between the impact analysis starting point and any impacted asset. The set of impacted assets is the same either way. However, the impact analysis diagram shows a network structure of impacts between the assets when assets have multiple incoming impacts; it shows a tree structure of impacts when assets have single incoming impacts.

By recording all the incoming impacts on each impacted asset the results are:

* expensive to search through in terms of CPU usage
* expensive to insert and delete all the relatively redundant impacts in the database
* expensive to query and process for display and reporting of IA results

However, because the analysis results contain all non duplicate impacts, the display of the impacts in the IA diagram and the results of custom queries on the impact analysis are more complete.

Reducing the number of duplicate impacts on an asset:

* reduces collection search times done by IA processing
* reduces database processing
* improves display and reporting times for IA UI
* does not alter the lists and counts of impacted assets, just the impacts between them

Therefore, the impact analysis diagram for these abbreviated impact analysis results shows up as an incomplete tree instead of a complete network. Custom queries that traverse the impact anlaysis chain of impacts will not find all the paths of true impact to or from each asset.

You need to evaluate the effect of each option to determine if you want to reduce your recorded impacts to improve performance, and whether or not you mind the effect of abbreviated results in your impact analysis diagram or custom queries.

Configurable in wsaa-impact-analysis.xml:
Parameter: multiIncomingImpact: (true or false) for recording multiple or reduced incoming impacts on assets
Default: true, which is how impact analysis has worked in the past.