diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index 362c83e8f4b..9215927bb82 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -513,6 +513,8 @@ Release 2.6.0 - UNRELEASED
 
   OPTIMIZATIONS
 
+    HADOOP-10838. Byte array native checksumming. (James Thomas via todd)
+
   BUG FIXES
 
     HADOOP-10781. Unportable getgrouplist() usage breaks FreeBSD (Dmitry
diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/DataChecksum.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/DataChecksum.java
index c50ecfd64ed..27984b48c7e 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/DataChecksum.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/DataChecksum.java
@@ -339,6 +339,12 @@ public class DataChecksum implements Checksum {
       byte[] data, int dataOff, int dataLen,
       byte[] checksums, int checksumsOff, String fileName,
       long basePos) throws ChecksumException {
+
+    if (NativeCrc32.isAvailable()) {
+      NativeCrc32.verifyChunkedSumsByteArray(bytesPerChecksum, type.id,
+          checksums, checksumsOff, data, dataOff, dataLen, fileName, basePos);
+      return;
+    }
     
     int remaining = dataLen;
     int dataPos = 0;
diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/NativeCrc32.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/NativeCrc32.java
index 13b2c9a5816..26a5e9b10dd 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/NativeCrc32.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/NativeCrc32.java
@@ -59,6 +59,16 @@ class NativeCrc32 {
         data, data.position(), data.remaining(),
         fileName, basePos);
   }
+
+  public static void verifyChunkedSumsByteArray(int bytesPerSum,
+      int checksumType, byte[] sums, int sumsOffset, byte[] data,
+      int dataOffset, int dataLength, String fileName, long basePos)
+      throws ChecksumException {
+    nativeVerifyChunkedSumsByteArray(bytesPerSum, checksumType,
+        sums, sumsOffset,
+        data, dataOffset, dataLength,
+        fileName, basePos);
+  }
   
     private static native void nativeVerifyChunkedSums(
       int bytesPerSum, int checksumType,
@@ -66,6 +76,12 @@ class NativeCrc32 {
       ByteBuffer data, int dataOffset, int dataLength,
       String fileName, long basePos);
 
+    private static native void nativeVerifyChunkedSumsByteArray(
+      int bytesPerSum, int checksumType,
+      byte[] sums, int sumsOffset,
+      byte[] data, int dataOffset, int dataLength,
+      String fileName, long basePos);
+
   // Copy the constants over from DataChecksum so that javah will pick them up
   // and make them available in the native code header.
   public static final int CHECKSUM_CRC32 = DataChecksum.CHECKSUM_CRC32;
diff --git a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/util/NativeCrc32.c b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/util/NativeCrc32.c
index cba25fa3047..4bd69bc41d7 100644
--- a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/util/NativeCrc32.c
+++ b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/util/NativeCrc32.c
@@ -34,6 +34,10 @@
 
 #include "bulk_crc32.h"
 
+#define MBYTE 1048576
+#define MIN(X,Y) ((X) < (Y) ? (X) : (Y))
+#define MAX(X,Y) ((X) > (Y) ? (X) : (Y))
+
 static void throw_checksum_exception(JNIEnv *env,
     uint32_t got_crc, uint32_t expected_crc,
     jstring j_filename, jlong pos) {
@@ -177,6 +181,84 @@ JNIEXPORT void JNICALL Java_org_apache_hadoop_util_NativeCrc32_nativeVerifyChunk
   }
 }
 
+JNIEXPORT void JNICALL Java_org_apache_hadoop_util_NativeCrc32_nativeVerifyChunkedSumsByteArray
+  (JNIEnv *env, jclass clazz,
+    jint bytes_per_checksum, jint j_crc_type,
+    jarray j_sums, jint sums_offset,
+    jarray j_data, jint data_offset, jint data_len,
+    jstring j_filename, jlong base_pos)
+{
+  uint8_t *sums_addr;
+  uint8_t *data_addr;
+  uint32_t *sums;
+  uint8_t *data;
+  int crc_type;
+  crc32_error_t error_data;
+  int ret;
+  int numChecksumsPerIter;
+  int checksumNum;
+
+  if (unlikely(!j_sums || !j_data)) {
+    THROW(env, "java/lang/NullPointerException",
+      "input byte arrays must not be null");
+    return;
+  }
+  if (unlikely(sums_offset < 0 || data_offset < 0 || data_len < 0)) {
+    THROW(env, "java/lang/IllegalArgumentException",
+      "bad offsets or lengths");
+    return;
+  }
+  if (unlikely(bytes_per_checksum) <= 0) {
+    THROW(env, "java/lang/IllegalArgumentException",
+      "invalid bytes_per_checksum");
+    return;
+  }
+
+  // Convert to correct internal C constant for CRC type
+  crc_type = convert_java_crc_type(env, j_crc_type);
+  if (crc_type == -1) return; // exception already thrown
+
+  numChecksumsPerIter = MAX(1, MBYTE / bytes_per_checksum);
+  checksumNum = 0;
+  while (checksumNum * bytes_per_checksum < data_len) {
+    // Convert byte arrays to C pointers
+    sums_addr = (*env)->GetPrimitiveArrayCritical(env, j_sums, NULL);
+    data_addr = (*env)->GetPrimitiveArrayCritical(env, j_data, NULL);
+
+    if (unlikely(!sums_addr || !data_addr)) {
+      if (data_addr) (*env)->ReleasePrimitiveArrayCritical(env, j_data, data_addr, 0);
+      if (sums_addr) (*env)->ReleasePrimitiveArrayCritical(env, j_sums, sums_addr, 0);
+      THROW(env, "java/lang/OutOfMemoryError",
+        "not enough memory for byte arrays in JNI code");
+      return;
+    }
+
+    sums = (uint32_t *)(sums_addr + sums_offset) + checksumNum;
+    data = data_addr + data_offset + checksumNum * bytes_per_checksum;
+
+    // Setup complete. Actually verify checksums.
+    ret = bulk_verify_crc(data, MIN(numChecksumsPerIter * bytes_per_checksum,
+                                    data_len - checksumNum * bytes_per_checksum),
+                          sums, crc_type, bytes_per_checksum, &error_data);
+    (*env)->ReleasePrimitiveArrayCritical(env, j_data, data_addr, 0);
+    (*env)->ReleasePrimitiveArrayCritical(env, j_sums, sums_addr, 0);
+    if (unlikely(ret == INVALID_CHECKSUM_DETECTED)) {
+      long pos = base_pos + (error_data.bad_data - data) + checksumNum *
+        bytes_per_checksum;
+      throw_checksum_exception(
+        env, error_data.got_crc, error_data.expected_crc,
+        j_filename, pos);
+      return;
+    } else if (unlikely(ret != CHECKSUMS_VALID)) {
+      THROW(env, "java/lang/AssertionError",
+        "Bad response code from native bulk_verify_crc");
+      return;
+    }
+    checksumNum += numChecksumsPerIter;
+  }
+
+}
+
 /**
  * vim: sw=2: ts=2: et:
  */