The Historic Data settings apply to the historic data for database items that support historic data storage (database points, master station accumulators and some driver-specific items). This differs from event data and configuration changes data (see Historic and Archive Data). When enabled, the Historic Data feature creates historic files, with each historic file containing 1 week's worth of historic data for an individual item.
NOTE: Do not confuse the Historic Data settings with the Historic Files setting. The Historic Files setting allows you to enable or disable historic storage of reports and documents, for example, file upload reports and Crystal Reports reports (see Enable or Disable Historic Files).
The Historic Data settings are located in the Historic Configuration branch of the Server Configuration Tool:
You can use the Historic Data settings to:
- Enable or Disable Historic Data Storage
- Specify the Duration to Retain Historic Data Online
- Define the Archive Time for Historic Data
- Specify the Future Data Time for Historic Data
- Reduce the Size of the Historic Granule Index
- Define the Historic Group Size to Optimize Performance
- (see Enable or Disable Manual Historic Data Validation)
- Define whether Modified Data is Used when Processing Historic Data
- Define the Historic Data Cache Size
- Configuring the Cache Flush Time and Threshold Limits
- Define the Thread Pool Size.
Further Information