diff --git a/src/main/java/org/lmdbjava/Dbi.java b/src/main/java/org/lmdbjava/Dbi.java
@@ -81,10 +81,8 @@ public final class Dbi<T> {
    if (nativeCb) {
      this.ccb =
          (keyA, keyB) -> {
-            final T compKeyA = proxy.allocate();
-            final T compKeyB = proxy.allocate();
-            proxy.out(compKeyA, keyA);
-            proxy.out(compKeyB, keyB);
            final int result = this.comparator.compare(compKeyA, compKeyB);
            proxy.deallocate(compKeyA);
            proxy.deallocate(compKeyB);

diff --git a/src/test/java/org/lmdbjava/ComparatorTest.java b/src/test/java/org/lmdbjava/ComparatorTest.java
@@ -67,11 +67,12 @@ public static Object[] data() {
    final ComparatorRunner string = new StringRunner();
    final ComparatorRunner db = new DirectBufferRunner();
    final ComparatorRunner ba = new ByteArrayRunner();
    final ComparatorRunner bb = new ByteBufferRunner();
    final ComparatorRunner netty = new NettyRunner();
    final ComparatorRunner gub = new GuavaUnsignedBytes();
    final ComparatorRunner gsb = new GuavaSignedBytes();
-    return new Object[] {string, db, ba, bb, netty, gub, gsb};
  }

  private static byte[] buffer(final int... bytes) {
@@ -140,6 +141,16 @@ public int compare(final byte[] o1, final byte[] o2) {
    }
  }

  /** Tests {@link ByteBufferProxy}. */
  private static final class ByteBufferRunner implements ComparatorRunner {


diff --git a/src/test/java/org/lmdbjava/TestUtils.java b/src/test/java/org/lmdbjava/TestUtils.java
@@ -36,9 +36,13 @@ final class TestUtils {
  private TestUtils() {}

  static byte[] ba(final int value) {
-    final MutableDirectBuffer b = new UnsafeBuffer(new byte[4]);
-    b.putInt(0, value);
-    return b.byteArray();
  }

  static ByteBuffer bb(final int value) {