rdisp/vb_refresh_info is a SAP Parameter attribute which is used to control Elapsed time for refreshing update server info information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
This defines the time span after which the context of an update server
is redetermined. The following belong to the context:
The number of update work processes of the server
The codepage and DB node of the server The context of an update server
can only change by changes in the operating type. Therefore, the context
is read again only every hour.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.