A general warning: With the recent history changes implemented in the develop branch, starting from a fresh ODB and editing 
any history panel, on gets tons of errors and debug output from mhttpd:

MVOdb: Error: MIDAS db_get_value() at ODB path "/History/Display/Default/Trigger rate/Minimum" returned status 312
MVOdb: Error: MIDAS db_get_value() at ODB path "/History/Display/Default/Trigger rate/Minimum" returned status 312
MVOdb: Error: MIDAS db_get_value() at ODB path "/History/Display/Default/Trigger rate/Maximum" returned status 312
MVOdb: Error: MIDAS db_get_value() at ODB path "/History/Display/Default/Trigger rate/Maximum" returned status 312
MVOdb: Error: MIDAS db_get_value() at ODB path "/History/Display/Default/Trigger rate/Zero ylow" returned status 312
MVOdb: Error: MIDAS db_get_value() at ODB path "/History/Display/Default/Trigger rate/Log axis" returned status 312
MVOdb: Error: MIDAS db_get_value() at ODB path "/History/Display/Default/Trigger rate/Zero ylow" returned status 312
Load from ODB History/Display/Default/Trigger rate: hist plot: 2 variables
timescale: 1h, minimum: 0.000000, maximum: 0.000000, zero_ylow: 0, log_axis: 0, show_run_markers: 1, show_values: 1, 
show_fill: 1
var[0] event [System][Trigger per sec.] formula [], colour [#00AAFF] label [] factor 1.000000 offset 0.000000 voffset 
0.000000 order 10
var[1] event [System][Trigger kB per sec.] formula [], colour [#FF9000] label [] factor 1.000000 offset 0.000000 voffset 
0.000000 order 20



This has to be fixed by the original author. I strongly recommend to make such modifications on a separate branch not to 
break running experiments.

Stefan