The current hibernate indexing method using pagination can be slow for large datasets and, in particular, slows down as the indexing progresses. There's a forum thread about it at http://forums.opensymphony.com/thread.jspa?threadID=67326&tstart=0. I came up with an alternative indexing method using hibernates ScrollableResults solution which shows much better behaviour with large numbers of instances, and the code will be attached to this issue.