The parameters in the sections below are set at the system level and thus do not
apply to any specific component.
General
| Config | Meaning | Default | 
| heron.check.tmaster.location.interval.sec | The interval, in seconds, after which to check if the topology master location has been fetched or not | 120 | 
| heron.metrics.export.interval | The interval, in seconds, at which components export metrics to the topology’s Metrics Manager |  | 
Logging
| Config | Meaning | Default | 
| heron.logging.directory | The relative path to the logging directory | log-files | 
| heron.logging.maximum.size.mb | The maximum log file size (in megabytes) | 100 | 
| heron.logging.maximum.files | The maximum number of log files | 5 | 
| heron.logging.prune.interval.sec | The time interval, in seconds, at which Heron prunes log files | 300 | 
| heron.logging.flush.interval.sec | The time interval, in seconds, at which Heron flushes log files | 10 | 
| heron.logging.err.threshold | The threshold level to log error | 3 |