Placing requests on the common dump queue

A host that is participating in CDQ processing places its dump requests onto the CDQ for processing. The following considerations apply:

• To verify that a host is connected to the CDQ, issue the QUERY ACTIVE command, then look for CONNECTION STATUS of CONNECTED in message ARC1560I.
• HOLD DUMP (any type) issued on the host that issued the dump request places the request on the CDQ if the master scheduler is also not held, (WAIT type requests are failed if the master scheduler is held). Both WAIT and NOWAIT type requests are placed as the master scheduler is available to assign and process requests in the CDQ. Tasks for this host will subsequently not be assigned by the master scheduler for processing.
• HOLD DUMP (any type) issued on the master scheduler host prevents it from assigning and processing requests. Note that NOWAIT request types are placed on the CDQ even though dump was held on the master scheduler. To keep the master scheduler's responsibilities intact, that is, if you do not want tasks on the master scheduler host to be used by the CDQ, issue a SETSYS MAXDUMPTASKS(0) command instead of HOLD DUMP. Alternatively, you can transition the master scheduler responsibilities to another host with SETSYS CQUEUE(D(MSC(N)) prior to issuing the HOLD.
• HOLD DUMP (any type) issued on all the hosts in the CDQ places the master scheduler in the DISABLED state. Use the messages issued in response to the QUERY ACTIVE to verify this state. Note that the MASTER SCHEDULER STATUS is DISABLED(HELD). When DISABLED:
  • New WAIT request types are failed locally
  • New NOWAIT request types are queued locally
  • Queued WAIT request types in the CDQ master scheduler host are failed
• SETSYS MAXDUMPTASKS(0) issued on the host that issued the dump request places the request on the CDQ, but tasks will subsequently not be assigned by the master scheduler for processing.
• Any request that is not submitted to the master scheduler host (for example, due to errors) is placed on the local queue of the host that issued the request.
• Requests submitted on the master scheduler host are placed on its local queue.
• Requests that are sent to the master scheduler host from other members are placed on the local master scheduler queue and then selected to run locally on the master scheduler, or assigned to be processed on another member in the CDQ group.
• The default priority of WAIT dump requests over NOWAIT dump requests does not change with the CDQ. However, the ALTERPRI command does support change requests currently queued to the CDQ.