Memoize TRANSITIVE_TRAVERSAL nodes to save memory.

--
MOS_MIGRATED_REVID=105994907

1 files changed, 7 insertions, 2 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/TransitiveTraversalValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/TransitiveTraversalValue.java
index 05b3c6a32c..f5021c049d 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/TransitiveTraversalValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/TransitiveTraversalValue.java
@@ -16,6 +16,8 @@ package com.google.devtools.build.lib.skyframe;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Interner;
+import com.google.common.collect.Interners;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
@@ -39,7 +41,9 @@ import javax.annotation.Nullable;
 @Immutable
 @ThreadSafe
 public class TransitiveTraversalValue implements SkyValue {
-
+  
+  private static final Interner<SkyKey> KEY_INTERNER = Interners.newWeakInterner();
+  
   @Nullable private final ImmutableSet<String> providers;
   @Nullable private final String firstErrorMessage;
 
@@ -125,6 +129,7 @@ public class TransitiveTraversalValue implements SkyValue {
 
   @ThreadSafe
   public static SkyKey key(Label label) {
-    return new SkyKey(SkyFunctions.TRANSITIVE_TRAVERSAL, label);
+    // Intern in order to save memory.
+    return KEY_INTERNER.intern(new SkyKey(SkyFunctions.TRANSITIVE_TRAVERSAL, label));
   }
 }