diff --git a/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/CopyOnReadStatsMBean.java b/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/CopyOnReadStatsMBean.java
index bd825bb..b6bfa78 100644
--- a/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/CopyOnReadStatsMBean.java
+++ b/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/CopyOnReadStatsMBean.java
@@ -69,6 +69,8 @@ public interface CopyOnReadStatsMBean {
 
     String getLocalIndexSize();
 
+    long getLocalIndexDirSize();
+
     String[] getGarbageDetails();
 
     String getGarbageSize();
diff --git a/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/IndexCopier.java b/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/IndexCopier.java
index 33a687b..136dc71 100644
--- a/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/IndexCopier.java
+++ b/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/IndexCopier.java
@@ -547,6 +547,11 @@ public class IndexCopier implements CopyOnReadStatsMBean, Closeable {
     }
 
     @Override
+    public long getLocalIndexDirSize() {
+        return indexRootDirectory.getSize();
+    }
+
+    @Override
     public String[] getGarbageDetails() {
         return toArray(transform(failedToDeleteFiles.values(),
                 new Function<LocalIndexFile, String>() {
diff --git a/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/LuceneIndexEditorProvider.java b/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/LuceneIndexEditorProvider.java
index db5881f..5320a95 100644
--- a/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/LuceneIndexEditorProvider.java
+++ b/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/LuceneIndexEditorProvider.java
@@ -233,8 +233,8 @@ public class LuceneIndexEditorProvider implements IndexEditorProvider {
             if (propertyIndexUpdateCallback != null) {
                 callbacks.add(propertyIndexUpdateCallback);
             }
-            if (mbean != null && statisticsProvider != null) {
-                callbacks.add(new LuceneIndexStatsUpdateCallback(indexPath, mbean, statisticsProvider));
+            if (mbean != null && statisticsProvider != null && indexCopier != null) {
+                callbacks.add(new LuceneIndexStatsUpdateCallback(indexPath, mbean, statisticsProvider, indexCopier));
             }
 
             if (!callbacks.isEmpty()) {
diff --git a/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/LuceneIndexStatsUpdateCallback.java b/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/LuceneIndexStatsUpdateCallback.java
index ee737f0..b6e3d58 100644
--- a/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/LuceneIndexStatsUpdateCallback.java
+++ b/oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/LuceneIndexStatsUpdateCallback.java
@@ -22,6 +22,7 @@ import org.apache.jackrabbit.oak.api.CommitFailedException;
 import org.apache.jackrabbit.oak.api.PropertyState;
 import org.apache.jackrabbit.oak.plugins.index.search.PropertyDefinition;
 import org.apache.jackrabbit.oak.plugins.index.search.PropertyUpdateCallback;
+import org.apache.jackrabbit.oak.stats.CounterStats;
 import org.apache.jackrabbit.oak.stats.HistogramStats;
 import org.apache.jackrabbit.oak.stats.StatisticsProvider;
 import org.apache.jackrabbit.oak.stats.StatsOptions;
@@ -39,18 +40,21 @@ public class LuceneIndexStatsUpdateCallback implements PropertyUpdateCallback {
 
     private static final String NO_DOCS = "_NO_DOCS";
     private static final String INDEX_SIZE = "_INDEX_SIZE";
+    private static final String LOCAL_INDEX_DIR_SIZE = "LOCAL_INDEX_DIR_SIZE";
 
     private final Logger log = LoggerFactory.getLogger(getClass());
 
     private final String indexPath;
     private final LuceneIndexMBean luceneIndexMBean;
     private final StatisticsProvider statisticsProvider;
+    private final IndexCopier indexCopier;
 
     LuceneIndexStatsUpdateCallback(String indexPath, @NotNull LuceneIndexMBean luceneIndexMBean,
-                                   @NotNull StatisticsProvider statisticsProvider) {
+                                   @NotNull StatisticsProvider statisticsProvider, @NotNull IndexCopier indexCopier) {
         this.indexPath = indexPath;
         this.luceneIndexMBean = luceneIndexMBean;
         this.statisticsProvider = statisticsProvider;
+        this.indexCopier = indexCopier;
     }
 
     @Override
@@ -69,7 +73,17 @@ public class LuceneIndexStatsUpdateCallback implements PropertyUpdateCallback {
             HistogramStats indexSizeHistogram = statisticsProvider.getHistogram(indexPath + INDEX_SIZE, StatsOptions.METRICS_ONLY);
             indexSizeHistogram.update(indexSize);
 
+            long localIndexDirSize = indexCopier.getLocalIndexDirSize();
+
+            CounterStats indexDirectorySizeStats = statisticsProvider.getCounterStats(LOCAL_INDEX_DIR_SIZE, StatsOptions.DEFAULT);
+            long deltaInSize = localIndexDirSize - indexDirectorySizeStats.getCount();
+            if (deltaInSize != 0) {
+                indexDirectorySizeStats.inc(deltaInSize);
+                log.debug("index directory size stats updated; size {} delta {}", localIndexDirSize, deltaInSize);
+            }
+
             log.debug("{} stats updated; docCount {}, size {}", indexPath, docCount, indexSize);
+
         } catch (IOException e) {
             log.debug("could not update no_docs/index_size stats for index at {}", indexPath, e);
         }