[Truffle] Hash load balance and resize.

jruby · May 11, 2015 · 7c29362 · 7c29362
1 parent 855c25f
commit 7c29362
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Showing 3 changed files with 50 additions and 2 deletions.
diff --git a/truffle/src/main/java/org/jruby/truffle/nodes/core/hash/HashNodes.java b/truffle/src/main/java/org/jruby/truffle/nodes/core/hash/HashNodes.java
@@ -331,6 +331,7 @@ public Object setPackedArray(VirtualFrame frame, RubyHash hash, RubyString key,
         private final ConditionProfile foundProfile = ConditionProfile.createBinaryProfile();
         private final ConditionProfile bucketCollisionProfile = ConditionProfile.createBinaryProfile();
         private final ConditionProfile appendingProfile = ConditionProfile.createBinaryProfile();
+        private final ConditionProfile resizeProfile = ConditionProfile.createBinaryProfile();
 
         @Specialization(guards = {"isBucketsStorage(hash)", "!isRubyString(key)"})
         public Object setBuckets(VirtualFrame frame, RubyHash hash, Object key, Object value) {
@@ -346,10 +347,12 @@ public Object setBuckets(VirtualFrame frame, RubyHash hash, Object key, Object v
             final Entry entry = result.getEntry();
 
             if (foundProfile.profile(entry == null)) {
+                final Entry[] entries = (Entry[]) hash.getStore();
+
                 final Entry newEntry = new Entry(result.getHashed(), key, value);
 
                 if (bucketCollisionProfile.profile(result.getPreviousEntry() == null)) {
-                    ((Entry[]) hash.getStore())[result.getIndex()] = newEntry;
+                    entries[result.getIndex()] = newEntry;
                 } else {
                     result.getPreviousEntry().setNextInLookup(newEntry);
                 }
@@ -365,7 +368,15 @@ public Object setBuckets(VirtualFrame frame, RubyHash hash, Object key, Object v
 
                 hash.setLastInSequence(newEntry);
 
-                hash.setSize(hash.getSize() + 1);
+                final int newSize = hash.getSize() + 1;
+
+                hash.setSize(newSize);
+
+                // TODO CS 11-May-15 could store the next size for resize instead of doing a float operation each time
+
+                if (resizeProfile.profile(newSize / (double) entries.length > BucketsStrategy.MAX_LOAD_BALANCE)) {
+                    BucketsStrategy.resize(hash);
+                }
             } else {
                 entry.setKeyValue(result.getHashed(), key, value);
             }

diff --git a/truffle/src/main/java/org/jruby/truffle/runtime/hash/BucketsStrategy.java b/truffle/src/main/java/org/jruby/truffle/runtime/hash/BucketsStrategy.java
@@ -9,12 +9,15 @@
  */
 package org.jruby.truffle.runtime.hash;
 
+import com.oracle.truffle.api.CompilerDirectives;
 import org.jruby.truffle.runtime.core.RubyHash;
 
 import java.util.Arrays;
 
 public abstract class BucketsStrategy {
 
+    public static final double MAX_LOAD_BALANCE = 0.75;
+
     public static final int SIGN_BIT_MASK = ~(1 << 31);
 
     private static final int[] CAPACITIES = Arrays.copyOf(org.jruby.RubyHash.MRI_PRIMES, org.jruby.RubyHash.MRI_PRIMES.length - 1);
@@ -68,4 +71,36 @@ public static void addNewEntry(RubyHash hash, int hashed, Object key, Object val
         assert HashOperations.verifyStore(hash);
     }
 
+    @CompilerDirectives.TruffleBoundary
+    public static void resize(RubyHash hash) {
+        HashOperations.verifyStore(hash);
+
+        final int bucketsCount = capacityGreaterThan(hash.getSize()) * 2;
+        final Entry[] newEntries = new Entry[bucketsCount];
+
+        Entry entry = hash.getFirstInSequence();
+
+        while (entry != null) {
+            final int bucketIndex = getBucketIndex(entry.getHashed(), bucketsCount);
+            Entry previousInLookup = newEntries[bucketIndex];
+
+            if (previousInLookup == null) {
+                newEntries[bucketIndex] = entry;
+            } else {
+                while (previousInLookup.getNextInLookup() != null) {
+                    previousInLookup = previousInLookup.getNextInLookup();
+                }
+
+                previousInLookup.setNextInLookup(entry);
+            }
+
+            entry.setNextInLookup(null);
+            entry = entry.getNextInSequence();
+        }
+
+        hash.setStore(newEntries, hash.getSize(), hash.getFirstInSequence(), hash.getLastInSequence());
+
+        HashOperations.verifyStore(hash);
+    }
+
 }
diff --git a/truffle/src/main/java/org/jruby/truffle/runtime/hash/PackedArrayStrategy.java b/truffle/src/main/java/org/jruby/truffle/runtime/hash/PackedArrayStrategy.java
@@ -9,6 +9,7 @@
  */
 package org.jruby.truffle.runtime.hash;
 
+import com.oracle.truffle.api.CompilerDirectives;
 import org.jruby.truffle.runtime.core.RubyHash;
 import org.jruby.util.cli.Options;
 
@@ -77,6 +78,7 @@ public static void removeEntry(Object[] store, int n) {
         }
     }
 
+    @CompilerDirectives.TruffleBoundary
     public static void promoteToBuckets(RubyHash hash, Object[] store, int size) {
         final Entry[] buckets = new Entry[BucketsStrategy.capacityGreaterThan(size)];