[SPARK-11583] [CORE] MapStatus Using RoaringBitmap More Properly

This PR upgrade the version of RoaringBitmap to 0.5.10, to optimize the memory layout, will be much smaller when most of blocks are empty.

This PR is based on #9661 (fix conflicts), see all of the comments at https://github.com/apache/spark/pull/9661 .

Author: Kent Yao <yaooqinn@hotmail.com>
Author: Davies Liu <davies@databricks.com>
Author: Charles Allen <charles@allen-net.com>

Closes #9746 from davies/roaring_mapstatus.

core/src/main/scala/org/apache/spark/scheduler/MapStatus.scala

@@ -122,8 +122,7 @@ private[spark] class CompressedMapStatus(
 
 /**
  * A [[MapStatus]] implementation that only stores the average size of non-empty blocks,
- * plus a bitmap for tracking which blocks are empty.  During serialization, this bitmap
- * is compressed.
+ * plus a bitmap for tracking which blocks are empty.
  *
  * @param loc location where the task is being executed
  * @param numNonEmptyBlocks the number of non-empty blocks
@@ -194,6 +193,8 @@ private[spark] object HighlyCompressedMapStatus {
     } else {
       0
     }
+    emptyBlocks.trim()
+    emptyBlocks.runOptimize()
     new HighlyCompressedMapStatus(loc, numNonEmptyBlocks, emptyBlocks, avgSize)
   }
 }

core/src/main/scala/org/apache/spark/serializer/KryoSerializer.scala

@@ -17,7 +17,7 @@
 
 package org.apache.spark.serializer
 
-import java.io.{EOFException, IOException, InputStream, OutputStream, DataInput, DataOutput}
+import java.io.{DataInput, DataOutput, EOFException, IOException, InputStream, OutputStream}
 import java.nio.ByteBuffer
 import javax.annotation.Nullable
 
@@ -25,9 +25,9 @@ import scala.collection.JavaConverters._
 import scala.collection.mutable.ArrayBuffer
 import scala.reflect.ClassTag
 
-import com.esotericsoftware.kryo.{Kryo, KryoException, Serializer => KryoClassSerializer}
 import com.esotericsoftware.kryo.io.{Input => KryoInput, Output => KryoOutput}
 import com.esotericsoftware.kryo.serializers.{JavaSerializer => KryoJavaSerializer}
+import com.esotericsoftware.kryo.{Kryo, KryoException, Serializer => KryoClassSerializer}
 import com.twitter.chill.{AllScalaRegistrar, EmptyScalaKryoInstantiator}
 import org.apache.avro.generic.{GenericData, GenericRecord}
 import org.roaringbitmap.RoaringBitmap
@@ -38,8 +38,8 @@ import org.apache.spark.broadcast.HttpBroadcast
 import org.apache.spark.network.util.ByteUnit
 import org.apache.spark.scheduler.{CompressedMapStatus, HighlyCompressedMapStatus}
 import org.apache.spark.storage._
-import org.apache.spark.util.{Utils, BoundedPriorityQueue, SerializableConfiguration, SerializableJobConf}
 import org.apache.spark.util.collection.CompactBuffer
+import org.apache.spark.util.{BoundedPriorityQueue, SerializableConfiguration, SerializableJobConf, Utils}
 
 /**
  * A Spark serializer that uses the [[https://code.google.com/p/kryo/ Kryo serialization library]].

core/src/test/scala/org/apache/spark/scheduler/MapStatusSuite.scala

@@ -21,6 +21,7 @@ import org.apache.spark.storage.BlockManagerId
 
 import org.apache.spark.{SparkConf, SparkFunSuite}
 import org.apache.spark.serializer.JavaSerializer
+import org.roaringbitmap.RoaringBitmap
 
 import scala.util.Random
 
@@ -97,4 +98,34 @@ class MapStatusSuite extends SparkFunSuite {
     val buf = ser.newInstance().serialize(status)
     ser.newInstance().deserialize[MapStatus](buf)
   }
+
+  test("RoaringBitmap: runOptimize succeeded") {
+    val r = new RoaringBitmap
+    (1 to 200000).foreach(i =>
+      if (i % 200 != 0) {
+        r.add(i)
+      }
+    )
+    val size1 = r.getSizeInBytes
+    val success = r.runOptimize()
+    r.trim()
+    val size2 = r.getSizeInBytes
+    assert(size1 > size2)
+    assert(success)
+  }
+
+  test("RoaringBitmap: runOptimize failed") {
+    val r = new RoaringBitmap
+    (1 to 200000).foreach(i =>
+      if (i % 200 == 0) {
+        r.add(i)
+      }
+    )
+    val size1 = r.getSizeInBytes
+    val success = r.runOptimize()
+    r.trim()
+    val size2 = r.getSizeInBytes
+    assert(size1 === size2)
+    assert(!success)
+  }
 }

pom.xml

@@ -637,7 +637,7 @@
       <dependency>
         <groupId>org.roaringbitmap</groupId>
         <artifactId>RoaringBitmap</artifactId>
-        <version>0.4.5</version>
+        <version>0.5.11</version>
       </dependency>
       <dependency>
         <groupId>commons-net</groupId>