diff --git a/jps/jps-builders/src/org/jetbrains/jps/incremental/storage/AbstractStateStorage.java b/jps/jps-builders/src/org/jetbrains/jps/incremental/storage/AbstractStateStorage.java
index 6da5a613e651..9b7ba49e1749 100644
--- a/jps/jps-builders/src/org/jetbrains/jps/incremental/storage/AbstractStateStorage.java
+++ b/jps/jps-builders/src/org/jetbrains/jps/incremental/storage/AbstractStateStorage.java
@@ -34,7 +34,9 @@ public abstract class AbstractStateStorage<Key, T> {
 
   public void dropMemoryCache() {
     synchronized (myDataLock) {
-      myMap.dropMemoryCaches();
+      if (myMap.isDirty()) {
+        myMap.dropMemoryCaches();
+      }
     }
   }
 
diff --git a/jps/model/src/org/jetbrains/ether/dependencyView/PersistentMaplet.java b/jps/model/src/org/jetbrains/ether/dependencyView/PersistentMaplet.java
index b60661c8948d..b6fcaa713052 100644
--- a/jps/model/src/org/jetbrains/ether/dependencyView/PersistentMaplet.java
+++ b/jps/model/src/org/jetbrains/ether/dependencyView/PersistentMaplet.java
@@ -108,7 +108,9 @@ public class PersistentMaplet<K, V> implements Maplet<K, V> {
 
   public void flush(boolean memoryCachesOnly) {
     if (memoryCachesOnly) {
-      myMap.dropMemoryCaches();
+      if (myMap.isDirty()) {
+        myMap.dropMemoryCaches();
+      }
     }
     else {
       myMap.force();
diff --git a/jps/model/src/org/jetbrains/ether/dependencyView/PersistentMultiMaplet.java b/jps/model/src/org/jetbrains/ether/dependencyView/PersistentMultiMaplet.java
index b62eb72f2b76..3cfc2966da50 100644
--- a/jps/model/src/org/jetbrains/ether/dependencyView/PersistentMultiMaplet.java
+++ b/jps/model/src/org/jetbrains/ether/dependencyView/PersistentMultiMaplet.java
@@ -169,7 +169,9 @@ class PersistentMultiMaplet<K, V> implements MultiMaplet<K, V> {
 
   public void flush(boolean memoryCachesOnly) {
     if (memoryCachesOnly) {
-      myMap.dropMemoryCaches();
+      if (myMap.isDirty()) {
+        myMap.dropMemoryCaches();
+      }
     }
     else {
       myMap.force();