Make TypedSize.getEstimatedSize more accurate

Previously we excluded the size of the instance itself, which is
significant since this is used in grouped aggregations. Also, we only
included the logical size of the BlockBuilder rather than the full
retained size

presto-main/src/main/java/com/facebook/presto/operator/aggregation/TypedSet.java

@@ -19,6 +19,7 @@
 import com.facebook.presto.spi.type.Type;
 import com.facebook.presto.util.array.IntBigArray;
 import io.airlift.units.DataSize;
+import org.openjdk.jol.info.ClassLayout;
 
 import static com.facebook.presto.ExceededMemoryLimitException.exceededLocalLimit;
 import static com.facebook.presto.type.TypeUtils.hashPosition;
@@ -30,6 +31,7 @@
 
 public class TypedSet
 {
+ private static final int INSTANCE_SIZE = ClassLayout.parseClass(TypedSet.class).instanceSize();
  private static final float FILL_RATIO = 0.75f;
  private static final long FOUR_MEGABYTES = new DataSize(4, MEGABYTE).toBytes();
 
@@ -63,7 +65,7 @@ public TypedSet(Type elementType, int expectedSize)
 
  public long getEstimatedSize()
  {
- return elementBlock.getSizeInBytes() + blockPositionByHash.sizeOf();
+ return INSTANCE_SIZE + elementBlock.getRetainedSizeInBytes() + blockPositionByHash.sizeOf();
  }
 
  public boolean contains(Block block, int position)