If you have a catalog that includes millions of items and run out of memory during indexing, consider adjusting the gcCallingRangeSize property of the /atg/search/repository/BulkLoader component. This component controls how often Java garbage collection is called during indexing. The default interval is 10000 items. Decrease the setting to run garbage collection more frequently and reduce the risk of out of memory errors.

Note that this change will slow the indexing process somewhat.