artdaq

I just helped Patrick Tsang at protoDUNE work through an issue in which he tried to run a system without a Dispatcher (and the EBs taking care or disk writing). The system would clog up with events because the EventBuilders were configured to send data to the Dispatcher, and they couldn't do so.

The fix was to set nonblocking_sends: true, but we should also not block if the destinations block is empty.

I've copied the EB FHiCL below that caused the system to clog up when there was no Dispatcher.

[np04daq@np04-srv-001 2768]$ cat EventBuilder1.fcl 
# Produced from 'fhicl-dump' using:
#   Input  : /tmp/np04daq/tmp.nVBzpV4vTY
#   Policy : cet::filepath_maker
#   Path   : "FHICL_FILE_PATH" 

daq: {
   event_builder: {
      buffer_count: 20
      event_queue_wait_time: 30
      expected_fragments_per_event: 9
      max_event_size_bytes: 3e8
      print_event_store_stats: true
      request_address: "227.128.12.26" 
      request_port: 3001
      routing_token_config: {
         routing_master_hostname: "np04-srv-001" 
         routing_token_port: 11010
         use_routing_master: true
      }
      send_init_fragments: false
      send_requests: true
      sources: {
         s0: {
            host_map: [
               {
                  host: "np04-srv-012" 
                  portOffset: 9100
                  rank: 0
               },
               {
                  host: "np04-srv-011" 
                  portOffset: 9112
                  rank: 1
               },
               {
                  host: "np04-srv-011" 
                  portOffset: 9124
                  rank: 2
               },
               {
                  host: "np04-srv-011" 
                  portOffset: 9136
                  rank: 3
               },
               {
                  host: "np04-srv-011" 
                  portOffset: 9148
                  rank: 4
               },
               {
                  host: "np04-srv-011" 
                  portOffset: 9160
                  rank: 5
               },
               {
                  host: "np04-srv-011" 
                  portOffset: 9172
                  rank: 6
               },
               {
                  host: "np04-srv-011" 
                  portOffset: 9184
                  rank: 7
               },
               {
                  host: "np04-srv-011" 
                  portOffset: 9196
                  rank: 8
               },
               {
                  host: "np04-srv-001" 
                  portOffset: 9208
                  rank: 9
               }
            ]
            max_fragment_size_words: 5e7
            source_rank: 0
            transferPluginType: "Autodetect" 
         }
         s1: {
            max_fragment_size_words: 5e7
            source_rank: 1
            transferPluginType: "Autodetect" 
         }
         s2: {
            max_fragment_size_words: 5e7
            source_rank: 2
            transferPluginType: "Autodetect" 
         }
         s3: {
            max_fragment_size_words: 5e7
            source_rank: 3
            transferPluginType: "Autodetect" 
         }
         s4: {
            max_fragment_size_words: 5e7
            source_rank: 4
            transferPluginType: "Autodetect" 
         }
         s5: {
            max_fragment_size_words: 5e7
            source_rank: 5
            transferPluginType: "Autodetect" 
         }
         s6: {
            max_fragment_size_words: 5e7
            source_rank: 6
            transferPluginType: "Autodetect" 
         }
         s7: {
            max_fragment_size_words: 5e7
            source_rank: 7
            transferPluginType: "Autodetect" 
         }
         s8: {
            max_fragment_size_words: 5e7
            source_rank: 8
            transferPluginType: "Autodetect" 
         }
      }
      use_art: true
      verbose: true
   }
   metrics: {
      dim: {
         DIMServerName: "EventBuilder1" 
         DNSNode: "np04-srv-010.cern.ch" 
         DNSPort: 2505
         Verbose: false
         level: 5
         metricPluginType: "dim" 
         reporting_interval: 5
      }
   }
}
outputs: {
   normalOutput: {
      compressionLevel: 0
      fastCloning: false
      fileName: "/data0/np04_raw_run%06r_%#_dl1.root" 
      fileProperties: {
         maxEvents: 1000
         maxRuns: 1
         maxSize: 8e6
      }
      module_type: "RootOutput" 
   }
   rootNetOutput: {
      module_type: "RootNetOutput" 
   }
}
physics: {
   analyzers: {}
   filters: {}
   my_output_modules: [
      "rootNetOutput",
      "normalOutput" 
   ]
   producers: {}
}
process_name: "DAQ" 
services: {
   NetMonTransportServiceInterface: {
      destinations: {}
      routing_table_config: {
         use_routing_master: false
      }
      service_provider: "NetMonTransportService" 
   }
   scheduler: {
      errorOnFailureToPut: false
   }
}
source: {
   module_type: "DuneInput" 
   resume_after_timeout: true
   waiting_time: 2.5e6
}