diff --git a/jps/jps-builders/src/org/jetbrains/jps/cmdline/BuildSession.java b/jps/jps-builders/src/org/jetbrains/jps/cmdline/BuildSession.java
index 326d2d4e5558..52c769b62f39 100644
--- a/jps/jps-builders/src/org/jetbrains/jps/cmdline/BuildSession.java
+++ b/jps/jps-builders/src/org/jetbrains/jps/cmdline/BuildSession.java
@@ -354,7 +354,7 @@ final class BuildSession implements Runnable, CanceledStatus {
             LOG.info("Applying deleted path from fs event to artifacts: " + file.getPath());
           }
           for (ArtifactRootDescriptor rootDescriptor : descriptor)
-            pd.fsState.registerDeleted(rootDescriptor.getArtifactName(), rootDescriptor.getRootId().getArtifactId(), deleted,
+            pd.fsState.registerDeleted(rootDescriptor.getArtifactName(), rootDescriptor.getArtifactId(), deleted,
                                        artifactTimestamps);
         }
       }
diff --git a/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/ArtifactRootId.java b/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/ArtifactRootId.java
deleted file mode 100644
index 676c7b1e8490..000000000000
--- a/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/ArtifactRootId.java
+++ /dev/null
@@ -1,54 +0,0 @@
-package org.jetbrains.jps.incremental.artifacts;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-
-/**
- * @author nik
- */
-public class ArtifactRootId {
-  private final int myArtifactId;
-  private final int myRootIndex;
-
-  public ArtifactRootId(int artifactId, int rootIndex) {
-    myArtifactId = artifactId;
-    myRootIndex = rootIndex;
-  }
-
-  public ArtifactRootId(DataInput input) throws IOException {
-    myArtifactId = input.readInt();
-    myRootIndex = input.readInt();
-  }
-
-  public int getArtifactId() {
-    return myArtifactId;
-  }
-
-  public int getRootIndex() {
-    return myRootIndex;
-  }
-
-  public void save(DataOutput out) throws IOException {
-    out.writeInt(myArtifactId);
-    out.writeInt(myRootIndex);
-  }
-
-  @Override
-  public boolean equals(Object o) {
-    if (this == o) {
-      return true;
-    }
-    if (o == null || getClass() != o.getClass()) {
-      return false;
-    }
-
-    ArtifactRootId id = (ArtifactRootId)o;
-    return myArtifactId == id.myArtifactId && myRootIndex == id.myRootIndex;
-  }
-
-  @Override
-  public int hashCode() {
-    return 31 * myArtifactId + myRootIndex;
-  }
-}
diff --git a/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/ArtifactRootsIndex.java b/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/ArtifactRootsIndex.java
index 0a8559c2fc43..09710f334ae4 100644
--- a/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/ArtifactRootsIndex.java
+++ b/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/ArtifactRootsIndex.java
@@ -24,13 +24,11 @@ import java.util.*;
  */
 public class ArtifactRootsIndex {
   private MultiMap<File, ArtifactRootDescriptor> myRootToDescriptorMap;
-  private Map<ArtifactRootId, ArtifactRootDescriptor> myIdToDescriptorMap;
   private Map<JpsArtifact, ArtifactInstructionsBuilder> myInstructions;
 
   public ArtifactRootsIndex(JpsModel model, Project project, BuildDataManager manager, ModuleRootsIndex rootsIndex) {
     myRootToDescriptorMap = new MultiMap<File, ArtifactRootDescriptor>();
     myInstructions = new HashMap<JpsArtifact, ArtifactInstructionsBuilder>();
-    myIdToDescriptorMap = new HashMap<ArtifactRootId, ArtifactRootDescriptor>();
     ArtifactsBuildData data = manager.getArtifactsBuildData();
     for (JpsArtifact artifact : JpsArtifactService.getInstance().getArtifacts(model.getProject())) {
       int artifactId = data.getArtifactId(artifact);
@@ -44,7 +42,6 @@ public class ArtifactRootsIndex {
       for (Pair<ArtifactRootDescriptor, DestinationInfo> pair : builder.getInstructions()) {
         ArtifactRootDescriptor descriptor = pair.getFirst();
         myRootToDescriptorMap.putValue(descriptor.getRootFile(), descriptor);
-        myIdToDescriptorMap.put(descriptor.getRootId(), descriptor);
       }
     }
   }
diff --git a/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/instructions/ArtifactRootDescriptor.java b/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/instructions/ArtifactRootDescriptor.java
index 81031f4d385a..fcfff0a7e12f 100644
--- a/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/instructions/ArtifactRootDescriptor.java
+++ b/jps/jps-builders/src/org/jetbrains/jps/incremental/artifacts/instructions/ArtifactRootDescriptor.java
@@ -3,7 +3,6 @@ package org.jetbrains.jps.incremental.artifacts.instructions;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.jps.incremental.CompileContext;
 import org.jetbrains.jps.incremental.artifacts.ArtifactOutputToSourceMapping;
-import org.jetbrains.jps.incremental.artifacts.ArtifactRootId;
 import org.jetbrains.jps.incremental.artifacts.ArtifactSourceToOutputMapping;
 
 import java.io.File;
@@ -15,22 +14,24 @@ import java.io.IOException;
 public abstract class ArtifactRootDescriptor {
   protected final File myRoot;
   private final SourceFileFilter myFilter;
-  private final ArtifactRootId myRootId;
+  private final int myRootIndex;
+  private final int myArtifactId;
   private final String myArtifactName;
 
   protected ArtifactRootDescriptor(File root, @NotNull SourceFileFilter filter, int index, int artifactId, String artifactName) {
     myRoot = root;
     myFilter = filter;
+    myRootIndex = index;
+    myArtifactId = artifactId;
     myArtifactName = artifactName;
-    myRootId = new ArtifactRootId(artifactId, index);
   }
 
   public final String getArtifactName() {
     return myArtifactName;
   }
 
-  public final ArtifactRootId getRootId() {
-    return myRootId;
+  public int getArtifactId() {
+    return myArtifactId;
   }
 
   @NotNull
@@ -48,6 +49,6 @@ public abstract class ArtifactRootDescriptor {
   }
 
   public int getRootIndex() {
-    return myRootId.getRootIndex();
+    return myRootIndex;
   }
 }
diff --git a/jps/jps-builders/src/org/jetbrains/jps/incremental/fs/BuildFSState.java b/jps/jps-builders/src/org/jetbrains/jps/incremental/fs/BuildFSState.java
index 7078e29cc5ca..42ea86c2875f 100644
--- a/jps/jps-builders/src/org/jetbrains/jps/incremental/fs/BuildFSState.java
+++ b/jps/jps-builders/src/org/jetbrains/jps/incremental/fs/BuildFSState.java
@@ -200,7 +200,7 @@ public class BuildFSState extends FSState {
         }
         else {
           marked = true;
-          storage.update(descriptor.getRootId().getArtifactId(), path, stamp);
+          storage.update(descriptor.getArtifactId(), path, stamp);
         }
       }
     }
diff --git a/jps/jps-builders/src/org/jetbrains/jps/incremental/fs/FSState.java b/jps/jps-builders/src/org/jetbrains/jps/incremental/fs/FSState.java
index fe37825d982d..d08b2689b07a 100644
--- a/jps/jps-builders/src/org/jetbrains/jps/incremental/fs/FSState.java
+++ b/jps/jps-builders/src/org/jetbrains/jps/incremental/fs/FSState.java
@@ -117,7 +117,7 @@ public class FSState {
 
   public void markDirty(ArtifactRootDescriptor descriptor, String filePath, ArtifactSourceTimestampStorage timestamps) throws IOException {
     markRecompile(descriptor, filePath);
-    timestamps.removeTimestamp(filePath, descriptor.getRootId().getArtifactId());
+    timestamps.removeTimestamp(filePath, descriptor.getArtifactId());
   }
 
   public void markRecompile(ArtifactRootDescriptor descriptor, String filePath) {