diff --git a/.idea/dictionaries/bashor.xml b/.idea/dictionaries/bashor.xml
index f44edba8ebd..fa362eaa919 100644
--- a/.idea/dictionaries/bashor.xml
+++ b/.idea/dictionaries/bashor.xml
@@ -2,8 +2,9 @@
   <dictionary name="bashor">
     <words>
       <w>ctor</w>
+      <w>interner</w>
       <w>lookups</w>
       <w>unescape</w>
     </words>
   </dictionary>
-</component>
+</component>
\ No newline at end of file
diff --git a/build-common/src/org/jetbrains/kotlin/incremental/LookupStorage.kt b/build-common/src/org/jetbrains/kotlin/incremental/LookupStorage.kt
index 680a9879826..4c691b500e1 100644
--- a/build-common/src/org/jetbrains/kotlin/incremental/LookupStorage.kt
+++ b/build-common/src/org/jetbrains/kotlin/incremental/LookupStorage.kt
@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.incremental
 
 import com.intellij.util.containers.MultiMap
+import com.intellij.util.containers.StringInterner
 import org.jetbrains.annotations.TestOnly
 import org.jetbrains.kotlin.incremental.components.LookupTracker
 import org.jetbrains.kotlin.incremental.components.Position
@@ -62,8 +63,7 @@ open class LookupStorage(private val targetDataDir: File) : BasicMapsOwner() {
         }
     }
 
-    fun addAll(lookups: Set<Map.Entry<LookupSymbol, Collection<String>>>) {
-        val allPaths = lookups.flatMapTo(HashSet<String>()) { it.value }
+    fun addAll(lookups: Set<Map.Entry<LookupSymbol, Collection<String>>>, allPaths: Set<String>) {
         val pathToId = allPaths.keysToMap { addFileIfNeeded(File(it)) }
 
         for ((lookupSymbol, paths) in lookups) {
@@ -183,13 +183,19 @@ open class LookupStorage(private val targetDataDir: File) : BasicMapsOwner() {
 
 class LookupTrackerImpl(private val delegate: LookupTracker) : LookupTracker {
     val lookups = MultiMap<LookupSymbol, String>()
+    val pathInterner = StringInterner()
+    private val interner = StringInterner()
 
     override val requiresPosition: Boolean
         get() = delegate.requiresPosition
 
     override fun record(filePath: String, position: Position, scopeFqName: String, scopeKind: ScopeKind, name: String) {
-        lookups.putValue(LookupSymbol(name, scopeFqName), filePath)
-        delegate.record(filePath, position, scopeFqName, scopeKind, name)
+        val internedScopeFqName = interner.intern(scopeFqName)
+        val internedName = interner.intern(name)
+        val internedFilePath = pathInterner.intern(filePath)
+
+        lookups.putValue(LookupSymbol(internedName, internedScopeFqName), internedFilePath)
+        delegate.record(internedFilePath, position, internedScopeFqName, scopeKind, internedName)
     }
 }
 
diff --git a/compiler/daemon/src/org/jetbrains/kotlin/daemon/RemoteLookupTrackerClient.kt b/compiler/daemon/src/org/jetbrains/kotlin/daemon/RemoteLookupTrackerClient.kt
index 3599055250c..047e02d419b 100644
--- a/compiler/daemon/src/org/jetbrains/kotlin/daemon/RemoteLookupTrackerClient.kt
+++ b/compiler/daemon/src/org/jetbrains/kotlin/daemon/RemoteLookupTrackerClient.kt
@@ -16,26 +16,32 @@
 
 package org.jetbrains.kotlin.daemon
 
+import com.intellij.util.containers.StringInterner
+import org.jetbrains.kotlin.daemon.common.CompilerCallbackServicesFacade
+import org.jetbrains.kotlin.daemon.common.DummyProfiler
+import org.jetbrains.kotlin.daemon.common.Profiler
 import org.jetbrains.kotlin.incremental.components.LookupInfo
 import org.jetbrains.kotlin.incremental.components.LookupTracker
 import org.jetbrains.kotlin.incremental.components.Position
 import org.jetbrains.kotlin.incremental.components.ScopeKind
-import org.jetbrains.kotlin.daemon.common.CompilerCallbackServicesFacade
-import org.jetbrains.kotlin.daemon.common.DummyProfiler
-import org.jetbrains.kotlin.daemon.common.Profiler
 
 
 class RemoteLookupTrackerClient(val facade: CompilerCallbackServicesFacade, val eventManger: EventManger, val profiler: Profiler = DummyProfiler()) : LookupTracker {
     private val isDoNothing = profiler.withMeasure(this) { facade.lookupTracker_isDoNothing() }
 
     private val lookups = hashSetOf<LookupInfo>()
+    private val interner = StringInterner()
 
     override val requiresPosition: Boolean = profiler.withMeasure(this) { facade.lookupTracker_requiresPosition() }
 
     override fun record(filePath: String, position: Position, scopeFqName: String, scopeKind: ScopeKind, name: String) {
         if (isDoNothing) return
 
-        lookups.add(LookupInfo(filePath, position, scopeFqName, scopeKind, name))
+        val internedFilePath = interner.intern(filePath)
+        val internedScopeFqName = interner.intern(scopeFqName)
+        val internedName = interner.intern(name)
+
+        lookups.add(LookupInfo(internedFilePath, position, internedScopeFqName, scopeKind, internedName))
     }
 
     init {
diff --git a/jps-plugin/src/org/jetbrains/kotlin/jps/build/KotlinBuilder.kt b/jps-plugin/src/org/jetbrains/kotlin/jps/build/KotlinBuilder.kt
index 6ab0bf66423..62773565ebb 100644
--- a/jps-plugin/src/org/jetbrains/kotlin/jps/build/KotlinBuilder.kt
+++ b/jps-plugin/src/org/jetbrains/kotlin/jps/build/KotlinBuilder.kt
@@ -542,7 +542,7 @@ class KotlinBuilder : ModuleLevelBuilder(BuilderCategory.SOURCE_PROCESSOR) {
         val removedFiles = chunk.targets.flatMap { KotlinSourceFileCollector.getRemovedKotlinFiles(dirtyFilesHolder, it) }
         removedFiles.forEach { lookupStorage.removeLookupsFrom(it) }
 
-        lookupStorage.addAll(lookupTracker.lookups.entrySet())
+        lookupStorage.addAll(lookupTracker.lookups.entrySet(), lookupTracker.pathInterner.values)
     }
 
     // if null is returned, nothing was done
diff --git a/jps-plugin/test/org/jetbrains/kotlin/jps/build/AbstractLookupTrackerTest.kt b/jps-plugin/test/org/jetbrains/kotlin/jps/build/AbstractLookupTrackerTest.kt
index 28455f8773a..bf79ec43766 100644
--- a/jps-plugin/test/org/jetbrains/kotlin/jps/build/AbstractLookupTrackerTest.kt
+++ b/jps-plugin/test/org/jetbrains/kotlin/jps/build/AbstractLookupTrackerTest.kt
@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.jps.build
 
 import com.intellij.openapi.util.io.FileUtil
+import com.intellij.util.containers.StringInterner
 import org.jetbrains.kotlin.incremental.components.LookupInfo
 import org.jetbrains.kotlin.incremental.components.LookupTracker
 import org.jetbrains.kotlin.incremental.components.Position
@@ -119,12 +120,17 @@ abstract class AbstractLookupTrackerTest : AbstractIncrementalJpsTest(
 
 class TestLookupTracker : LookupTracker {
     val lookups = arrayListOf<LookupInfo>()
+    private val interner = StringInterner()
 
     override val requiresPosition: Boolean
         get() = true
 
     override fun record(filePath: String, position: Position, scopeFqName: String, scopeKind: ScopeKind, name: String) {
-        lookups.add(LookupInfo(filePath, position, scopeFqName, scopeKind, name))
+        val internedFilePath = interner.intern(filePath)
+        val internedScopeFqName = interner.intern(scopeFqName)
+        val internedName = interner.intern(name)
+
+        lookups.add(LookupInfo(internedFilePath, position, internedScopeFqName, scopeKind, internedName))
     }
 }