Simultaneously updating and viewing an IODF

Imagine that both users UserA and UserB invoke the Channel Subsystem List of the same IODF. UserA wants to delete channel subsystems CSS 1 and CSS 3, and UserB wants to work with the partitions of CSS 1.

                      UserA:                  |                      UserB:
                                              |
            Channel Subsystem List            |             Channel Subsystem List
                                              |
  Processor ID . . . : BBBX                   |   Processor ID . . . : BBBX
                                              |
    CSS Devices in SS0    Devices in SS1      |     CSS Devices in SS0    Devices in SS1
  / ID  Maximum + Actual  Maximum + Actual    |   / ID  Maximum + Actual  Maximum + Actual
                                              |
  _ 0   65280     28      65535     0         |   _ 0   65280     28      65535     0
 d  1   65280     28      65535     0         |  p  1   65280     28      65535     0
  _ 2   65280     0       65535     0         |   _ 2   65280     0       65535     0
 d  3   65280     0       65535     0         |   _ 3   65280     0       65535     0
 

Both users press Enter. While UserA sees the updated Channel Subsystem List, UserB sees the partitions of the meanwhile deleted CSS 1, because he still views the state of the IODF as loaded from storage. He will get a refreshed view after applying an update on the IODF.

                      UserA:                  |                      UserB:
                                              |
            Channel Subsystem List            |                Partition List
                                              |
  Processor ID . . . : BBBX                   | Processor ID  . . . . : BBBX
                                              | Configuration mode  . : LPAR
    CSS Devices in SS0    Devices in SS1      | Channel Subsystem ID  : 1
  / ID  Maximum + Actual  Maximum + Actual    |
                                              | / Partition Name   Number Usage
  _ 0   65280     28      65535     0         | _ PART11           1      CF/OS
  _ 2   65280     0       65535     0         | _ PART12           2      CF/OS
                                              | _ PART13           3      CF/OS