Lucene index deleted when opening with Luke/Indexreader

I was creating a lucene index when my indexing progra开发者_如何学编程m crashed. The indexer had processed about 3M documents before crashing, producing a 14GB file. When I opened the index in Luke (with force unlock), the whole index was gone!. poof.

The opened index had 0 documents and its size was reduced to 1kb. Did anyone experience this, or can offer an explanation

(Using Lucene.Net 2.9)

Most probably, your indexing code never called commit() before crashing. If you don't want to lose all your changes, you should call commit() every X added documents.