List of Current Metrics

This is a list of all the metrics currently being tracked by the DDT nearline scripts and the people responsible for them. If you have questions about any of the metrics listed here, please contact the author of the metric in question.

Please note that, unless otherwise stated, these details are subject to change. This is particularly true while the DDT monitoring framework is being constructed.

Trigger Rates


Kyle Thomsen


This metric tracks each trigger's average rate for each subrun versus time.


  1. The length of the subrun is obtained from the ROOT files produced by vanilla OnMon's processing. The way that that processing is done dictates that the subrun start and end times are obtained exclusively from the cosmic data stream. However, using the subrun start and end times reported in the DDT files for this purpose results in extremely long subrun lengths and erratic rates. Thus, using the same information as vanilla nearline not only ensures that the rates are calculated using the correct subrun lengths but also provides a consistency in the calculations going on behind the scenes, which is always a plus when it comes to monitoring.
  2. The number of counts for each trigger is determined by integrating over all bins corresponding to each trigger bit within the histogram TriggerVsHourGeneral. The details of how this histogram is built within the processing step are located in OnlineMonitoring/producer/TriggerPlots.cxx, though all that really matters is that it bins vertically by trigger bit and horizontally by minute over the last day, of which only the minute(s) corresponding to the subrun's duration might have any entries.
  3. After the count for a trigger is tallied, this value is divided by the subrun length.
  4. This value is then plotted against the subrun's start time.


This is currently the only metric tracked by DDT nearline, and it is only being run over data from the FD.

The plots produced by this metric agree quite well with the corresponding plots on Ganglia.