@Override
    public void toData(DataOutput out,
        SerializationContext context) throws IOException {
      super.toData(out, context);
      DataSerializer.writeArrayList(grantors, out);
      DataSerializer.writeArrayList(grantorVersions, out);
      DataSerializer.writeArrayList(grantorSerialNumbers, out);
      DataSerializer.writeArrayList(nonGrantors, out);
    }
Note the synchronization; we can only process one response at a time.
geode-core/src/main/java/org/apache/geode/distributed/internal/locks/ElderInitProcessor.java