Page History

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• Name
  
  • The name of the History Store.
• Enabled
  
  • Checkbox to enable/disable the History Store. Not selected by default.
• Type
  • The type of History Store.
  • Data stored in an In_-Memory History Store will not be persisted across a module disable/enable, module restart or power loss. 
  • Data stored in a Disk-Backed History Store will persist across a module disable/enable, module restart or power loss.
• Edge Node Tag Capacity
  • Maximum number of Edge Node level tag change events to store per Edge Node before dropping oldest historical Edge Node tag change events. This value is independent of the 'Device Tag Capacity' and only applies to how many 'Edge Node level' tag change events are stored per Edge Node.
  • A tag change event is triggered by either a change in value or quality and results in the tag's Qualified Value (which has three attributes of value, quality and timestamp) being stored. 
• Device Tag Capacity
  
  • Maximum number of Device tag change events to store per Device before dropping oldest historical Device tag change events. This value is independent of the 'Edge Node Tag Capacity' and only applies to how many 'Device level' tag change events are stored per Device.
  • A tag change event is triggered by either a change in value or quality and results in the tag's Qualified Value (which has three attributes of value, quality and timestamp) being stored.
• Flush Quantity
  • The maximum number of tags to publish in a single message upon reestablishing communication.
• Flush Period
  • The period to wait in milliseconds between publishes when flushing messages upon reestablishing communication

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