Changing context
The Plex ID and SMF ID fields, which are located in the upper right corner of a workspace, display the currently selected plex and subsystem or region. If these fields are displayed in green, you can overtype them to switch the context to view data for another plex or subsystem.
For example, in the workspace shown below, you can overtype the SYS value in the SMF ID field with the SMF ID for another LPAR, then press Enter to see data for that LPAR instead of SYS.

If these fields are blue, they cannot be overwritten.