Apache Lucene.Net 2.4.0 Class Library API

IndexWriter.MaybeMerge Method 

Expert: asks the mergePolicy whether any merges are necessary now and if so, runs the requested merges and then iterate (test again if merges are needed) until no more merges are returned by the mergePolicy. Explicit calls to MaybeMerge() are usually not necessary. The most common case is when merge policy parameters have changed.

public void MaybeMerge();

See Also

IndexWriter Class | Lucene.Net.Index Namespace