memleak: Add example for label and another example usage.

memleak/memory-consumption-over-time.gp

@@ -14,6 +14,7 @@
 #     - default: 1 tic every hour.
 #     -    long: 1 tic every 6 hours.
 # Example usage: ./memory-consumption-over-time.gp myprogram 2021-12-05T08:42
+# Example usage: ./memory-consumption-over-time.gp myprogram 2021-12-05T08:42 big short 640 480
 
 if (ARGC < 2) {
     printerr "You probably want to supply the program name ", \
@@ -99,6 +100,9 @@ set output sprintf("%s memory consumption over time.svg", myprog)
 
 set y2range [0:]              # Don't go into minus if Swap is 0 the whole time.
 
+# set label 1 '1 hour 200 MiB' at (1*60*60),(204800/1024) offset first 0,0 \
+#     point pt 7 lc "red"
+
 plot infile every 4::0 using ((timecolumn(2) - mystarttime)):($3/1024) title 'USS' \
      with linespoints linewidth 3 pointtype 7 pointsize 0.5, \
      \