diff --git a/platform/lang-impl/src/com/intellij/util/indexing/IndexingStamp.java b/platform/lang-impl/src/com/intellij/util/indexing/IndexingStamp.java
index fc0b917cd8c0..55e9f3b39ebe 100644
--- a/platform/lang-impl/src/com/intellij/util/indexing/IndexingStamp.java
+++ b/platform/lang-impl/src/com/intellij/util/indexing/IndexingStamp.java
@@ -509,6 +509,22 @@ public final class IndexingStamp {
 
   public static void flushCache(@Nullable Integer finishedFile) {
     if (finishedFile != null && finishedFile == INVALID_FILE_ID) finishedFile = 0;
+
+    if (finishedFile != null) {
+      Lock readLock = getStripedLock(finishedFile).readLock();
+      readLock.lock();
+      try {
+        Timestamps timestamps = ourTimestampsCache.get(finishedFile);
+        if (timestamps == null) return;
+        if (!timestamps.isDirty()) {
+          ourTimestampsCache.remove(finishedFile);
+          return;
+        }
+      } finally {
+        readLock.unlock();
+      }
+    }
+
     // todo make better (e.g. FinishedFiles striping, remove integers)
     while (finishedFile == null || !ourFinishedFiles.offer(finishedFile)) {
       List<Integer> files = new ArrayList<>(ourFinishedFiles.size());
diff --git a/platform/lang-impl/src/com/intellij/util/indexing/UnindexedFilesFinder.java b/platform/lang-impl/src/com/intellij/util/indexing/UnindexedFilesFinder.java
index 06726aed6f69..60d56c87fa8a 100644
--- a/platform/lang-impl/src/com/intellij/util/indexing/UnindexedFilesFinder.java
+++ b/platform/lang-impl/src/com/intellij/util/indexing/UnindexedFilesFinder.java
@@ -60,8 +60,9 @@ final class UnindexedFilesFinder implements VirtualFileFilter {
 
       IndexedFileImpl indexedFile = new IndexedFileImpl(file, myProject);
       if (file instanceof VirtualFileSystemEntry && ((VirtualFileSystemEntry)file).isFileIndexed()) {
+        int inputId = Math.abs(FileBasedIndexImpl.getIdMaskingNonIdBasedFile(file));
+
         if (myRunExtensionsForFilesMarkedAsIndexed && myShouldProcessUpToDateFiles) {
-          int inputId = Math.abs(FileBasedIndexImpl.getIdMaskingNonIdBasedFile(file));
           List<ID<?, ?>> ids = IndexingStamp.getNontrivialFileIndexedStates(inputId);
           for (FileBasedIndexInfrastructureExtension.FileIndexingStatusProcessor processor : myStateProcessors) {
             for (ID<?, ?> id : ids) {
@@ -74,6 +75,7 @@ final class UnindexedFilesFinder implements VirtualFileFilter {
           }
         }
         if (!shouldIndexFile.get()) {
+          IndexingStamp.flushCache(inputId);
           return false;
         }
       }