diff --git a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/input/record/CharArrayRecord.java b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/input/record/CharArrayRecord.java
index 6b8e10d..f174962 100644
--- a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/input/record/CharArrayRecord.java
+++ b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/input/record/CharArrayRecord.java
@@ -69,10 +69,8 @@
                 throw new IOException(
                         "Record is too large!. Maximum record size is " + ExternalDataConstants.MAX_RECORD_SIZE);
             }
-            int newSize = len + ExternalDataConstants.DEFAULT_BUFFER_INCREMENT;
-            if (newSize > ExternalDataConstants.MAX_RECORD_SIZE) {
-                newSize = ExternalDataConstants.MAX_RECORD_SIZE;
-            }
+            int newSize = Math.min((int)(len * ExternalDataConstants.DEFAULT_BUFFER_INCREMENT_FACTOR),
+                    ExternalDataConstants.MAX_RECORD_SIZE);
             value = Arrays.copyOf(value, newSize);
         }
     }
diff --git a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/input/record/reader/hdfs/AbstractCharRecordLookupReader.java b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/input/record/reader/hdfs/AbstractCharRecordLookupReader.java
index 45d01e9..f9ec114 100644
--- a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/input/record/reader/hdfs/AbstractCharRecordLookupReader.java
+++ b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/input/record/reader/hdfs/AbstractCharRecordLookupReader.java
@@ -64,7 +64,7 @@
         reusableByteBuffer.clear();
         if (reusableByteBuffer.remaining() < value.getLength()) {
             reusableByteBuffer = ByteBuffer
-                    .allocateDirect(value.getLength() + ExternalDataConstants.DEFAULT_BUFFER_INCREMENT);
+                    .allocateDirect((int)(value.getLength() * ExternalDataConstants.DEFAULT_BUFFER_INCREMENT_FACTOR));
         }
         reusableByteBuffer.put(value.getBytes(), 0, value.getLength());
         reusableByteBuffer.flip();
diff --git a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/ExternalDataConstants.java b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/ExternalDataConstants.java
index 0fd76cc..cf2b7f3 100644
--- a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/ExternalDataConstants.java
+++ b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/ExternalDataConstants.java
@@ -206,7 +206,7 @@
      * Size default values
      */
     public static final int DEFAULT_BUFFER_SIZE = 4096;
-    public static final int DEFAULT_BUFFER_INCREMENT = 2048;
+    public static final float DEFAULT_BUFFER_INCREMENT_FACTOR = 1.5F;
     public static final int DEFAULT_QUEUE_SIZE = 64;
     public static final int MAX_RECORD_SIZE = 32000000;