As a server, the importance of the holder address space TAURHLD should be set below TCPIP but above the scheduler address space TAURISPF. This setting comes into play when TAURHLD starts up and terminates or when commands are executed against the holder address space.
The scheduler and the user server address spaces should have the same importance, with the user servers classified like any TSO user address space using the response time goal of TSO. All transactions executing within scheduler and user server are TSO transactions.
Keep in mind that these address spaces are STCs, so the classification must be done under the STC subsystem.