Renamed FastLongHash to ReorganizingLongHash and updated the default …

…initial capacity Signed-off-by: Ketan Verma <[email protected]>
opensearch-project · Jun 16, 2023 · bc6f294 · bc6f294
1 parent 4e86707
commit bc6f294
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Showing 4 changed files with 21 additions and 17 deletions.
diff --git a/benchmarks/src/main/java/org/opensearch/common/util/LongHashBenchmark.java b/benchmarks/src/main/java/org/opensearch/common/util/LongHashBenchmark.java
@@ -20,7 +20,7 @@
 import org.openjdk.jmh.annotations.State;
 import org.openjdk.jmh.annotations.Warmup;
 import org.openjdk.jmh.infra.Blackhole;
-import org.opensearch.common.lease.Releasable;
+import org.opensearch.core.common.lease.Releasable;
 
 import java.util.Random;
 import java.util.concurrent.TimeUnit;
@@ -48,7 +48,7 @@ public void add(Blackhole bh, HashTableOptions tableOpts, WorkloadOptions worklo
     @State(Scope.Benchmark)
     public static class HashTableOptions {
 
-        @Param({ "LongHash", "FastLongHash" })
+        @Param({ "LongHash", "ReorganizingLongHash" })
         public String type;
 
         @Param({ "1" })
@@ -65,8 +65,8 @@ public void setup() {
                 case "LongHash":
                     supplier = this::newLongHash;
                     break;
-                case "FastLongHash":
-                    supplier = this::newFastLongHash;
+                case "ReorganizingLongHash":
+                    supplier = this::newReorganizingLongHash;
                     break;
                 default:
                     throw new IllegalArgumentException("invalid hash table type: " + type);
@@ -93,9 +93,13 @@ public void close() {
             };
         }
 
-        private HashTable newFastLongHash() {
+        private HashTable newReorganizingLongHash() {
             return new HashTable() {
-                private final FastLongHash table = new FastLongHash(initialCapacity, loadFactor, BigArrays.NON_RECYCLING_INSTANCE);
+                private final ReorganizingLongHash table = new ReorganizingLongHash(
+                    initialCapacity,
+                    loadFactor,
+                    BigArrays.NON_RECYCLING_INSTANCE
+                );
 
                 @Override
                 public long add(long key) {

diff --git a/.../opensearch/common/util/FastLongHash.java → ...rch/common/util/ReorganizingLongHash.java b/.../opensearch/common/util/FastLongHash.java → ...rch/common/util/ReorganizingLongHash.java
@@ -9,7 +9,7 @@
 package org.opensearch.common.util;
 
 import org.apache.lucene.util.hppc.BitMixer;
-import org.opensearch.common.lease.Releasable;
+import org.opensearch.core.common.lease.Releasable;
 
 /**
  * Specialized hash table implementation that maps a (primitive) long to long.
@@ -25,9 +25,9 @@
  *
  * @opensearch.internal
  */
-public class FastLongHash implements Releasable {
+public class ReorganizingLongHash implements Releasable {
     private static final long MAX_CAPACITY = 1L << 32;
-    private static final long DEFAULT_INITIAL_CAPACITY = 1;
+    private static final long DEFAULT_INITIAL_CAPACITY = 32;
     private static final float DEFAULT_LOAD_FACTOR = 0.6f;
 
     /**
@@ -99,11 +99,11 @@ public class FastLongHash implements Releasable {
     private static final long MASK_PSL = 0x7FFF000000000000L;  // extract PSL
     private static final long INCR_PSL = 0x0001000000000000L;  // increment PSL by one
 
-    public FastLongHash(final BigArrays bigArrays) {
+    public ReorganizingLongHash(final BigArrays bigArrays) {
         this(DEFAULT_INITIAL_CAPACITY, DEFAULT_LOAD_FACTOR, bigArrays);
     }
 
-    public FastLongHash(long initialCapacity, final float loadFactor, final BigArrays bigArrays) {
+    public ReorganizingLongHash(final long initialCapacity, final float loadFactor, final BigArrays bigArrays) {
         assert initialCapacity > 0 : "initial capacity must be greater than 0";
         assert loadFactor > 0 && loadFactor < 1 : "load factor must be between 0 and 1";
 

diff --git a/...er/src/main/java/org/opensearch/search/aggregations/bucket/terms/LongKeyedBucketOrds.java b/...er/src/main/java/org/opensearch/search/aggregations/bucket/terms/LongKeyedBucketOrds.java
@@ -33,7 +33,7 @@
 package org.opensearch.search.aggregations.bucket.terms;
 
 import org.opensearch.common.util.BigArrays;
-import org.opensearch.common.util.FastLongHash;
+import org.opensearch.common.util.ReorganizingLongHash;
 import org.opensearch.common.util.LongLongHash;
 import org.opensearch.core.common.lease.Releasable;
 import org.opensearch.search.aggregations.CardinalityUpperBound;
@@ -148,10 +148,10 @@ public long value() {
      * @opensearch.internal
      */
     public static class FromSingle extends LongKeyedBucketOrds {
-        private final FastLongHash ords;
+        private final ReorganizingLongHash ords;
 
         public FromSingle(BigArrays bigArrays) {
-            ords = new FastLongHash(bigArrays);
+            ords = new ReorganizingLongHash(bigArrays);
         }
 
         @Override

diff --git a/...search/common/util/FastLongHashTests.java → ...ommon/util/ReorganizingLongHashTests.java b/...search/common/util/FastLongHashTests.java → ...ommon/util/ReorganizingLongHashTests.java
@@ -13,13 +13,13 @@
 import java.util.HashMap;
 import java.util.Map;
 
-public class FastLongHashTests extends OpenSearchTestCase {
+public class ReorganizingLongHashTests extends OpenSearchTestCase {
 
     public void testFuzzy() {
         Map<Long, Long> reference = new HashMap<>();
 
         try (
-            FastLongHash h = new FastLongHash(
+            ReorganizingLongHash h = new ReorganizingLongHash(
                 randomIntBetween(1, 100),      // random capacity
                 0.6f + randomFloat() * 0.39f,  // random load factor to verify collision resolution
                 BigArrays.NON_RECYCLING_INSTANCE
@@ -61,7 +61,7 @@ public void testFuzzy() {
     }
 
     public void testRearrangement() {
-        try (FastLongHash h = new FastLongHash(4, 0.6f, BigArrays.NON_RECYCLING_INSTANCE) {
+        try (ReorganizingLongHash h = new ReorganizingLongHash(4, 0.6f, BigArrays.NON_RECYCLING_INSTANCE) {
             /**
              * Overriding with an "identity" hash function to make it easier to reason about the placement
              * of values in the hash table. The backing array of the hash table will have a size (8),