From b4ff37ebbcae8be4333951beb6b059e92b69ea4e Mon Sep 17 00:00:00 2001 From: Michael McCandless Date: Mon, 12 Sep 2011 16:16:18 +0000 Subject: [PATCH] clarify that IW.expungeDeletes relies on MP to determine merges git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1169816 13f79535-47bb-0310-9956-ffa450edef68 --- lucene/src/java/org/apache/lucene/index/IndexWriter.java | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/lucene/src/java/org/apache/lucene/index/IndexWriter.java b/lucene/src/java/org/apache/lucene/index/IndexWriter.java index 14a722a1342..fb8202620ff 100644 --- a/lucene/src/java/org/apache/lucene/index/IndexWriter.java +++ b/lucene/src/java/org/apache/lucene/index/IndexWriter.java @@ -1901,7 +1901,14 @@ public class IndexWriter implements Closeable, TwoPhaseCommit { } - /** Expunges all deletes from the index. When an index + /** Requests an expungeDeletes operation, by invoking + * {@link MergePolicy#findMergesToExpungeDeletes}. + * The MergePolicy determines what merges should be done. + * For example, the default {@link TieredMergePolicy} + * will only expunage deletes from a segment if the + * percentage of deleted docs is over 10%. + * + *

When an index * has many document deletions (or updates to existing * documents), it's best to either call optimize or * expungeDeletes to remove all unused data in the index