diff --git a/lucene/contrib/misc/src/java/org/apache/lucene/index/PKIndexSplitter.java b/lucene/contrib/misc/src/java/org/apache/lucene/index/PKIndexSplitter.java
index 398d99ddb7f..0ecc5fb784e 100644
--- a/lucene/contrib/misc/src/java/org/apache/lucene/index/PKIndexSplitter.java
+++ b/lucene/contrib/misc/src/java/org/apache/lucene/index/PKIndexSplitter.java
@@ -34,6 +34,7 @@ import org.apache.lucene.util.Version;
 /**
  * Split an index based on a {@link Filter}.
  */
+
 public class PKIndexSplitter {
   private final Filter docsInFirstIndex;
   private final Directory input;
diff --git a/lucene/src/java/org/apache/lucene/index/IndexWriter.java b/lucene/src/java/org/apache/lucene/index/IndexWriter.java
index ce421ca68dd..8817c7601bd 100644
--- a/lucene/src/java/org/apache/lucene/index/IndexWriter.java
+++ b/lucene/src/java/org/apache/lucene/index/IndexWriter.java
@@ -1674,11 +1674,13 @@ public class IndexWriter implements Closeable, TwoPhaseCommit {
       for(final MergePolicy.OneMerge merge  : pendingMerges) {
         merge.optimize = true;
         merge.maxNumSegmentsOptimize = maxNumSegments;
+        segmentsToOptimize.put(merge.info, Boolean.TRUE);
       }
 
       for ( final MergePolicy.OneMerge merge: runningMerges ) {
         merge.optimize = true;
         merge.maxNumSegmentsOptimize = maxNumSegments;
+        segmentsToOptimize.put(merge.info, Boolean.TRUE);
       }
     }
 
@@ -1891,7 +1893,6 @@ public class IndexWriter implements Closeable, TwoPhaseCommit {
     final MergePolicy.MergeSpecification spec;
     if (optimize) {
       spec = mergePolicy.findMergesForOptimize(segmentInfos, maxNumSegmentsOptimize, Collections.unmodifiableMap(segmentsToOptimize));
-
       if (spec != null) {
         final int numMerges = spec.merges.size();
         for(int i=0;i<numMerges;i++) {
@@ -3044,7 +3045,9 @@ public class IndexWriter implements Closeable, TwoPhaseCommit {
 
     if (merge.optimize) {
       // cascade the optimize:
-      segmentsToOptimize.put(merge.info, Boolean.FALSE);
+      if (!segmentsToOptimize.containsKey(merge.info)) {
+        segmentsToOptimize.put(merge.info, Boolean.FALSE);
+      }
     }
 
     return true;
diff --git a/lucene/src/java/org/apache/lucene/index/LogMergePolicy.java b/lucene/src/java/org/apache/lucene/index/LogMergePolicy.java
index 1fd30325274..8943ed72b2b 100644
--- a/lucene/src/java/org/apache/lucene/index/LogMergePolicy.java
+++ b/lucene/src/java/org/apache/lucene/index/LogMergePolicy.java
@@ -285,7 +285,7 @@ public abstract class LogMergePolicy extends MergePolicy {
   private MergeSpecification findMergesForOptimizeMaxNumSegments(SegmentInfos infos, int maxNumSegments, int last) throws IOException {
     MergeSpecification spec = new MergeSpecification();
     final List<SegmentInfo> segments = infos.asList();
-    
+
     // First, enroll all "full" merges (size
     // mergeFactor) to potentially be run concurrently:
     while (last - maxNumSegments + 1 >= mergeFactor) {
@@ -353,7 +353,7 @@ public abstract class LogMergePolicy extends MergePolicy {
 
     assert maxNumSegments > 0;
     if (verbose()) {
-      message("findMergesForOptimize: maxNumSegs=" + maxNumSegments + " segsToOptimize= "+ segmentsToOptimize);
+      message("findMergesForOptimize: maxNumSegs=" + maxNumSegments + " segsToOptimize="+ segmentsToOptimize);
     }
 
     // If the segments are already optimized (e.g. there's only 1 segment), or
@@ -401,7 +401,7 @@ public abstract class LogMergePolicy extends MergePolicy {
         break;
       }
     }
-    
+
     if (anyTooLarge) {
       return findMergesForOptimizeSizeLimit(infos, maxNumSegments, last);
     } else {