diff --git a/platform/platform-impl/src/com/intellij/openapi/fileTypes/impl/FileTypeManagerImpl.java b/platform/platform-impl/src/com/intellij/openapi/fileTypes/impl/FileTypeManagerImpl.java
index 83fa8dc423bf..5998c7e432a8 100644
--- a/platform/platform-impl/src/com/intellij/openapi/fileTypes/impl/FileTypeManagerImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/fileTypes/impl/FileTypeManagerImpl.java
@@ -206,7 +206,7 @@ public class FileTypeManagerImpl extends FileTypeManagerEx implements Persistent
             VirtualFile file = event instanceof VFileCreateEvent ? /* avoid expensive find child here */ null : event.getFile();
             VirtualFile filtered = file != null && wasAutoDetectedBefore(file) && isDetectable(file) ? file : null;
             if (toLog()) {
-              log("F: handled " + event + "; filtered file: " + filtered + "(file: "+file+"; wasAutoDetectedBefore(file): "+(file == null ? null : wasAutoDetectedBefore(file))+"; isDetectable(file): "+(file == null ? null : isDetectable(file))+"; file.getLength(): "+(file == null ? null : file.getLength())+"; file.isValid(): "+(file == null ? null : file.isValid())+"; file.is(VFileProperty.SPECIAL): "+(file == null ? null : file.is(VFileProperty.SPECIAL))+"; packedFlags.get(id): "+(!(file instanceof VirtualFileWithId) ? null : packedFlags.get(((VirtualFileWithId)file).getId()))+"; file.getFileSystem():"+(file == null ? null : file.getFileSystem())+")");
+              log("F: handled " + event + "; filtered file: " + filtered + " (file: "+file+"; wasAutoDetectedBefore(file): "+(file == null ? null : wasAutoDetectedBefore(file))+"; isDetectable(file): "+(file == null ? null : isDetectable(file))+"; file.getLength(): "+(file == null ? null : file.getLength())+"; file.isValid(): "+(file == null ? null : file.isValid())+"; file.is(VFileProperty.SPECIAL): "+(file == null ? null : file.is(VFileProperty.SPECIAL))+"; packedFlags.get(id): "+(!(file instanceof VirtualFileWithId) ? null : packedFlags.get(((VirtualFileWithId)file).getId()))+"; file.getFileSystem():"+(file == null ? null : file.getFileSystem())+")");
             }
             return filtered;
           }
@@ -349,7 +349,11 @@ public class FileTypeManagerImpl extends FileTypeManagerEx implements Persistent
         int id = file instanceof VirtualFileWithId ? ((VirtualFileWithId)file).getId() : -1;
         FileType before = getAutoDetectedType(file, id);
 
-        packedFlags.set(id, ATTRIBUTES_WERE_LOADED_MASK);
+        int flags = ATTRIBUTES_WERE_LOADED_MASK;
+        packedFlags.set(id, flags);
+        if (toLog()) {
+          log("F: reDetect("+file.getName()+") prepare to redetect. flags: "+flags);
+        }
 
         file.putUserData(DETECTED_FROM_CONTENT_FILE_TYPE_KEY, null);
         FileType after = getFileTypeByFile(file); // may be back to standard file type
@@ -481,13 +485,16 @@ public class FileTypeManagerImpl extends FileTypeManagerEx implements Persistent
       if (autoDetectWasRun) {
         FileType type = getAutoDetectedType(file, id);
         if (toLog()) {
-          log("F: autodetected getFileType("+file.getName()+") = "+type.getName());
+          log("F: autodetected getFileType("+file.getName()+") = "+type.getName()+"; packedFlags.get(id):"+flags);
         }
         return type;
       }
       if ((flags & ATTRIBUTES_WERE_LOADED_MASK) == 0) {
         flags = readFlagsFromCache(file);
         packedFlags.set(id, flags);
+        if (toLog()) {
+          log("F: readFlagsFromCache("+file.getName()+") = "+flags);
+        }
       }
       boolean wasDetectedAsText = BitUtil.isSet(flags, AUTO_DETECTED_AS_TEXT_MASK);
       boolean wasDetectedAsBinary = BitUtil.isSet(flags, AUTO_DETECTED_AS_BINARY_MASK);
@@ -553,6 +560,9 @@ public class FileTypeManagerImpl extends FileTypeManagerEx implements Persistent
     autoDetectedAttribute = autoDetectedAttribute.newVersion(count);
     PropertiesComponent.getInstance().setValue("fileTypeChangedCounter", Integer.toString(count));
     packedFlags.clear();
+    if (toLog()) {
+      log("F: clearCaches");
+    }
   }
 
   @NotNull
@@ -583,6 +593,9 @@ public class FileTypeManagerImpl extends FileTypeManagerEx implements Persistent
       flags = BitUtil.set(flags, AUTO_DETECTED_AS_TEXT_MASK, wasAutodetectedAsText);
       flags = BitUtil.set(flags, AUTO_DETECTED_AS_BINARY_MASK, wasAutodetectedAsBinary);
       packedFlags.set(id, flags);
+      if (toLog()) {
+        log("F: cacheAutoDetectedFileType("+file.getName()+") = "+flags);
+      }
 
       if (wasAutodetectedAsText || wasAutodetectedAsBinary) {
         file.putUserData(DETECTED_FROM_CONTENT_FILE_TYPE_KEY, null);