if (writeRequest.getMessage() instanceof IoBuffer) {
IoBuffer buffer = (IoBuffer) writeRequest.getMessage();
// I/O processor implementation will call buffer.reset()
// it after the write operation is finished, because
// the buffer will be specified with messageSent event.
buffer.mark();
int remaining = buffer.remaining();
if (remaining == 0) {
// Zero-sized buffer means the internal message
// delimiter.
s.increaseScheduledWriteMessages();