The following italicized excerpt is from the IBM InfoCenter for IBM Business Monitor 8. This is the direct content as written by IBM:
To maintain dashboard performance and ensure that your system runs efficiently, you can purge, archive, export, and import instance data for a monitor model version. The following scenarios explains the benefits of the purging and archiving function: Scenario one:
Your IBM® Business Monitor server has run for a long period of time.
The dashboard becomes slow due to the amount of data.
You archive data on a one-time or periodic basis.
The dashboard’s performance improves because there is less data to report on.
Optionally, you can move the archived data to an environment dedicated to historical analysis or to a data warehouse.
You have run the monitor model for a period of time and have some terminated instances and some active instances.
You show the dashboard with the existing terminated and active instances, and are satisfied with the results.
You export the terminated and active instances into the flat files as the backup.
You want to show the same dashboard later, and so you import the instances.
You can purge instance data and archive it on a one-time basis or set it up as a scheduled service. Scheduled service can be found under Applications > Monitor Services > Monitor Model > Scheduled Services > Purge and Archive Instance Data. Here you can set up the frequency of running the service.
Click on Version > Model Version. Here you can set up the data you want to purge based on a given number of days, as well as, the location of where to create the CSV files that will contain the purged data.