+completely off.
+
+Note that the <tt>threshold</tt> keyword can be abbreviated here. For example,
+all the following notations have the same result.
+\verbatim
+--log=root.threshold:debug
+--log=root.threshol:debug
+--log=root.thresho:debug
+--log=root.thresh:debug
+--log=root.thres:debug
+--log=root.thre:debug
+--log=root.thr:debug
+--log=root.th:debug
+--log=root.t:debug
+--log=root.:debug <--- That's obviously really ugly, but it actually works.
+\endverbatim
+
+The full list of recognized thresholds is the following: