how much jdbc datamodel is slow

[deneche abdelhakim]

I am trying to run an item based recommender on movielens 100k example,
I'am looping through a quarter of the items calling
recommender.getMostSimilarItems(10) for each of them. The FileDataModel
takes no more than 5s but the MySQLJDBCDataModel requires more than 300s.
Is this expected ?