forceMergeDeletes

Forces merging of all segments that have deleted documents. The actual merges to be executed are determined by the MergePolicy. For example, the default TieredMergePolicy will only pick a segment if the percentage of deleted docs is over 10%.

This is often a horribly costly operation; rarely is it warranted.

To see how many deletions you have pending in your index, call .

NOTE: this method first flushes a new segment (if there are indexed documents), and applies all buffered deletes.