Analyze the output for outstanding sysplex messages

If the pfs_qualifier field displayed in the MOUNT LATCH ACTIVITY, FILE SYSTEM LATCH ACTIVITY, or FILE LATCH ACTIVITY table shows XSYS Message to: sysname, the operation causing the wait is happening on another system in the sysplex indicated by sysname. Do the following steps:

The information displayed under the OUTSTANDING CROSS SYSTEM MESSAGES: heading in message BPXO063I shows more information about the message sent to the other system (see Figure 1). You can identify the message sent by the task holding the latch by the matching ASID and TCB values from the holding task and the task under the OUTSTANDING CROSS SYSTEM MESSAGES: heading. Note and retain the TCB and ASID value of the message for the next step in this procedure:
Figure 1. Example: OUTSTANDING CROSS SYSTEM MESSAGES section
```
OUTSTANDING CROSS SYSTEM MESSAGES:                                    
 SENT SYSPLEX MESSAGES:                                               
    USER   ASID   TCB    FCODE  MEMBER   REQID     MSG TYPE     AGE   
  MEGA     0025 008DD218  0008 SY2      01000038 LookupCall   00.03.08
  TC0      0026 008E6E88  1011 SY1      0100003A Quiesce      00.00.05
  OMVS     000E 008E9828  0804 SY2      01000039 VfsInactCall 00.01.18
 RECEIVED SYSPLEX MESSAGES:                                           
           FROM   FROM           FROM                                 
   ON TCB  ASID   TCB    FCODE  MEMBER   REQID     MSG TYPE     AGE   
  008D97C8 0026 008E6E88  1011 SY1      0100003A Quiesce      00.00.05
     IS DOING:  Mount Latch Wait                   
```
If pipes are used, the output from sysplex messages might not have a corresponding sent sysplex messages. The system that received the request replied to the user so that resources are released and continued processing. On the sender side, once the reply has been received, the task goes into an OSI wait where it will wait to be posted. Because this is a pipes task, the waiter is not shown in the other waiters table, which makes it difficult to correlate between the systems that received the message and the system where it originated. In these cases, the ReqID will be blank. In that situation, using the SPECIAL filtering option (D OMVS,W,S) might result in the corresponding waiter.
On the remote system where the message is sent, issue D OMVS,WAITERS and look in the RECEIVED SYSPLEX MESSAGES section for a message with the matching TCB and ASID. The ASID and TCB fields should also match those of the sending thread. Use the value of the IS DOING: field on the remote system to continue contention analysis and resolve the contention.