diff --git a/common/src/main/scala/org/apache/comet/vector/StreamReader.scala b/common/src/main/scala/org/apache/comet/vector/StreamReader.scala
index 61d800bfb5..4a08f05213 100644
--- a/common/src/main/scala/org/apache/comet/vector/StreamReader.scala
+++ b/common/src/main/scala/org/apache/comet/vector/StreamReader.scala
@@ -30,8 +30,9 @@ import org.apache.spark.sql.vectorized.ColumnarBatch
 /**
  * A reader that consumes Arrow data from an input channel, and produces Comet batches.
  */
-case class StreamReader(channel: ReadableByteChannel) extends AutoCloseable {
+case class StreamReader(channel: ReadableByteChannel, source: String) extends AutoCloseable {
   private var allocator = new RootAllocator(Long.MaxValue)
+    .newChildAllocator(s"${this.getClass.getSimpleName}/$source", 0, Long.MaxValue)
   private val channelReader = new MessageChannelReader(new ReadChannel(channel), allocator)
   private var arrowReader = new ArrowStreamReader(channelReader, allocator)
   private var root = arrowReader.getVectorSchemaRoot
diff --git a/common/src/main/scala/org/apache/spark/sql/comet/execution/shuffle/ArrowReaderIterator.scala b/common/src/main/scala/org/apache/spark/sql/comet/execution/shuffle/ArrowReaderIterator.scala
index 304c3ce779..3c0fa153d8 100644
--- a/common/src/main/scala/org/apache/spark/sql/comet/execution/shuffle/ArrowReaderIterator.scala
+++ b/common/src/main/scala/org/apache/spark/sql/comet/execution/shuffle/ArrowReaderIterator.scala
@@ -25,9 +25,10 @@ import org.apache.spark.sql.vectorized.ColumnarBatch
 
 import org.apache.comet.vector._
 
-class ArrowReaderIterator(channel: ReadableByteChannel) extends Iterator[ColumnarBatch] {
+class ArrowReaderIterator(channel: ReadableByteChannel, source: String)
+    extends Iterator[ColumnarBatch] {
 
-  private val reader = StreamReader(channel)
+  private val reader = StreamReader(channel, source)
   private var batch = nextBatch()
   private var currentBatch: ColumnarBatch = null
 
diff --git a/common/src/main/scala/org/apache/spark/sql/comet/execution/shuffle/CometBlockStoreShuffleReader.scala b/common/src/main/scala/org/apache/spark/sql/comet/execution/shuffle/CometBlockStoreShuffleReader.scala
index b461b53f54..2026dfc5c5 100644
--- a/common/src/main/scala/org/apache/spark/sql/comet/execution/shuffle/CometBlockStoreShuffleReader.scala
+++ b/common/src/main/scala/org/apache/spark/sql/comet/execution/shuffle/CometBlockStoreShuffleReader.scala
@@ -108,7 +108,7 @@ class CometBlockStoreShuffleReader[K, C](
               // Closes previous read iterator.
               currentReadIterator.close()
             }
-            currentReadIterator = new ArrowReaderIterator(channel)
+            currentReadIterator = new ArrowReaderIterator(channel, "shuffle reader")
             currentReadIterator.map((0, _)) // use 0 as key since it's not used
           }
       }
diff --git a/spark/src/main/scala/org/apache/spark/sql/comet/CometBroadcastExchangeExec.scala b/spark/src/main/scala/org/apache/spark/sql/comet/CometBroadcastExchangeExec.scala
index a8322be7d9..f0d235800c 100644
--- a/spark/src/main/scala/org/apache/spark/sql/comet/CometBroadcastExchangeExec.scala
+++ b/spark/src/main/scala/org/apache/spark/sql/comet/CometBroadcastExchangeExec.scala
@@ -284,7 +284,7 @@ class CometBatchRDD(
 
   override def compute(split: Partition, context: TaskContext): Iterator[ColumnarBatch] = {
     val partition = split.asInstanceOf[CometBatchPartition]
-    partition.value.value.toIterator.flatMap(CometExec.decodeBatches)
+    partition.value.value.toIterator.flatMap(CometExec.decodeBatches(_, "broadcast"))
   }
 }
 
diff --git a/spark/src/main/scala/org/apache/spark/sql/comet/operators.scala b/spark/src/main/scala/org/apache/spark/sql/comet/operators.scala
index 1065367c27..03be652297 100644
--- a/spark/src/main/scala/org/apache/spark/sql/comet/operators.scala
+++ b/spark/src/main/scala/org/apache/spark/sql/comet/operators.scala
@@ -78,7 +78,7 @@ abstract class CometExec extends CometPlan {
     val countsAndBytes = CometExec.getByteArrayRdd(this).collect()
     val total = countsAndBytes.map(_._1).sum
     val rows = countsAndBytes.iterator
-      .flatMap(countAndBytes => CometExec.decodeBatches(countAndBytes._2))
+      .flatMap(countAndBytes => CometExec.decodeBatches(countAndBytes._2, "collect"))
     (total, rows)
   }
 }
@@ -118,7 +118,7 @@ object CometExec {
   /**
    * Decodes the byte arrays back to ColumnarBatchs and put them into buffer.
    */
-  def decodeBatches(bytes: ChunkedByteBuffer): Iterator[ColumnarBatch] = {
+  def decodeBatches(bytes: ChunkedByteBuffer, source: String): Iterator[ColumnarBatch] = {
     if (bytes.size == 0) {
       return Iterator.empty
     }
@@ -127,7 +127,7 @@ object CometExec {
     val cbbis = bytes.toInputStream()
     val ins = new DataInputStream(codec.compressedInputStream(cbbis))
 
-    new ArrowReaderIterator(Channels.newChannel(ins))
+    new ArrowReaderIterator(Channels.newChannel(ins), source)
   }
 }