Running the Hlt in DaVinci, 2010

In order to run the Hlt in DaVinci, it is at a minimum necessary to specify a threshold settings which configure the Hlt. These can be found in the HltSettings package and each setting also specifies which L0 configuration is associated to the Hlt setting in question.

     from Configurables import DaVinci
     DaVinci().Hlt = True
     DaVinci().HltThresholdSettings = 'Physics_LoadsaEventsThankYouVeryMuch'
If you wish to re-run the L0, it is necessary to specify that you are Overruling the value specified in the Hlt settings and that you wish to Replace the existing L0 banks on your datafile with the output of the offline L0 emulation.
     DaVinci().OverruleL0TCK = '0xBlaBla' 
     DaVinci().ReplaceL0BanksWithEmulated = True
The list of L0 TCKs which can be entered in place of "0xBlaBla" above can be found in the L0DU package in the options folder. Not all the L0 TCKs are compatible with all the Hlt threshold settings. For running in 2010 you will be mostly interested in L0 TCK "0x1710" which is the default L0 TCK for physics data taking in the pit.

Each Hlt setting assumes a single corresponding L0 TCK. Sometimes, however, you do not want to reemulate the L0 TCK but you wish to rerun the Hlt on some data collected with more than one L0 TCK -- typically if you are running on real data taken early in 2010. By default, the Hlt will exit the job if it finds that an event was recorded with an L0 TCK different from the one specified in the Hlt settings. However, it is possible to tell the Hlt to ignore this

     from Configurables import HltConf
     HltConf().ForceSingleL0Configuration = False
Note that this may or may not work; some L0 TCK combinations are genuinely incompatible with each other and cannot be processed with the same Hlt setting. You will have to know in advance which L0 TCKs will be found on your input files and verify that they are compatible with the Hlt setting which you wish to use.

It is useful to turn on the monitoring of the Hlt algorithms, like so.

     HltConf().EnableMonitoring = True
     HltConf().HistogrammingLevel = 'Everything'

-- VladimirGligorov - 16-Jun-2010

This topic: LHCb > LHCbTrigger > RunningTheHlt
Topic revision: r1 - 2010-06-16 - VladimirGligorov
This site is powered by the TWiki collaboration platform Powered by PerlCopyright & 2008-2019 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback