The use of cache mechanism is effective when a large number of parts are present in the tree structure in BOM Transformer or Service Associative Part Structure Browser (SAPSB). The advantage of using cache mechanism is that after the initial loading of the structure in cache, the subsequent actions are executed relatively faster. You can use this mechanism to boost the performance of BOM Transformer.

The prerequisite to leveraging the cache mechanism is setting the user preference Enable Structure Cache to Yes. With this configuration, the entire structure information of a session is stored in cache. After the preference is configured, the process of building a cache starts in the background when you open a BOM Transformer session. A separate cache is built for every BOM Transformer session. The time taken to build a cache depends on the size of the structure.

The cache is updated when changes are made to a subassembly, an assembly, or a part. The cache is incrementally updated only for that subassembly and not for the entire structure. The cache is rebuilt if the root node is changed.

The upstream and downstream tree structure of BOM Transformer have separate caches and both are updated independently. When you modify a structure in downstream, only the downstream cache is updated. While the downstream cache is being updated, you can modify the upstream structure. However, PTC recommends that you invoke a user action on the structure only after the cache building process is complete. During the cache building process in downstream, if you invoke an action in upstream that has an impact on the downstream structure, the action will be executed only after the cache building process in the downstream is completed. For example, Select Equivalent Parts on Other Side.

The status on the cache building process is displayed below the BOM Transformer toolbar. The following table provides information about the status messages of the cache building process:

The process of building cache may fail due to the presence of recursive paths in the structure. Recursive path occurs when a child part references its parent part. Rectify the structure before you rebuild the cache.

The following actions use cache:

The following actions result in updating the structure information and rebuilding the cache: