             orig_cb?(err, result)
 
         # Finally, do the query.
+        query_queue_exec.label('sent').inc()
         @_do_query(opts)
 
     _update: (state) =>

        tm = new Date()
        @_do_one_query opts, =>
            state.count -= 1
            state.time_ms.push(new Date() - tm)
            if state.time_ms.length > TIME_HISTORY_LENGTH
                state.time_ms.shift()
            @_info(state)

        return s / v.length

    _info: (state) =>
        query_queue_count.labels(state.client_id).set(state.count)
        @_dbg("client_id='#{state.client_id}': avg=#{@_avg(state)}ms, count=#{state.count}, queued.length=#{state.queue?.length}, sent=#{state.sent}")
