+ /*
+ * The relay daemon control protocol expects a rotation
+ * position as "the sequence number of the first packet
+ * _after_ the current trace chunk.
+ *
+ * At the moment when the positions of the buffers are
+ * sampled, the production position does not necessarily
+ * sit at a packet boundary. The 'active' flush
+ * operation above will push the production position to
+ * the next packet boundary _if_ it is not already
+ * sitting at such a boundary.
+ *
+ * Assuming a current production position that is not
+ * on the bound of a packet, the 'target' sequence
+ * number is
+ * (consumed_pos / subbuffer_size) + 1
+ * Note the '+ 1' to ensure the current packet is
+ * part of the current trace chunk.
+ *
+ * However, if the production position is already at
+ * a packet boundary, the '+ 1' is not necessary as the
+ * last packet of the current chunk is already
+ * 'complete'.
+ */