PH67605: BATCH REMOVE REQUEST FAILED RESPONSE (EXCEPTION) - REASON (METHOD_FAILED) WHEN REMOVING BUNDLES VIA BATCHREP.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• During application deployment in the production environment, a
  problem occurs when attempting to remove bundle definitions
  using REXX scripts with the REMOVE OBJECT(BUNDDEF) command. The
  operation returns a response code 1029 (FAILED) and reason code
  1359 (EXCEPTION), even though the bundle appears to be
  successfully removed.
  
  This issue also occurs when removing bundles via BATCHREP and
  the WUI.
  
  The problem occurs with the BAS Version Control cache list,
  which is used to ensure that the same resource/name/version
  triplet cannot be defined more than once within the CICSplex.
  That list is created in memory from the data repository during
  CMAS startup. Because the data is inherently ordered at this
  point (based on the VSAM record keys) the list can be built in
  an optimised fashion, but doing so leaves the resulting B+ tree
  unbalanced. The expectation is that a subsequent add or remove
  operation against the list should perform some rebalancing, but
  a logic error means that is failing in this case.
  
  The deletion of the BUNDDEF from the data repository is actually
  taking effect. The error reported on the API operation is
  reflecting the fact that the attempt to rebalance the tree
  failed.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICSPlex SM Users.                       *
  ****************************************************************
  * PROBLEM DESCRIPTION: CPSM Remove requests for BAS resource   *
  *                      definitions return with RESPONSE        *
  *                      1029 (FAILED), REASON 1359 (EXCEPTION)  *
  *                      but the definitions are removed.        *
  ****************************************************************
  * RECOMMENDATION: The PTFs addressing this APAR should be      *
  *                 applied to all CMAS regions and the regions  *
  *                 restarted. The restarts may be completed in  *
  *                 any order.                                   *
  ****************************************************************
  BAS resource when a CMAS region is operating with
  com.ibm.cics.cpsm.bas.largecicsplex support enabled (explicitly
  via feature toggle in 6.1, or default in 6.2+) are held within
  a B+ tree structure internally in the BAS cache list. When a
  CMAS is restarted with this structure, the tree is bulk loaded,
  that can result in one leaf node having less keys in than the
  other nodes. If a REMOVE request is made for a BAS resource in
  this node, and after the element is removed, the node element
  count goes below the minimum count, processing is used to move
  elements (steal) from other sibling nodes to maintain
  approximate equal capacity across nodes for performance and
  operation of the B+ tree.
  
  Due to incorrect logic in this processing in the bulk load
  scenario (where no BAS resources have been defined or modified
  since last CMAS restart prior to the REMOVE and a specific
  element count to fill some but not all nodes), it is unable to
  move enough keys between nodes to bring the count above this
  minimum level. As other nodes are also full, nodes cannot be
  merged. As such though the element has been removed, and the
  BAS definition is removed from the CICSplex, as this processing
  fails to balance the leaf nodes, an exception occurs and
  the REMOVE gets the bad response though the item is removed.
  
  In this case method XCX3 produces an exception trace record
  with for MERGENDE, i.e. :
  METHOD:XCX3   PRIOR:XCLR    DEBUG:MERGENDE  POINTID:   143
  MAJOBJ:CHE    ENVRN:CMAS    TYPE:EXCEPTION
  

Problem conclusion

• The steal logic, to balance B+ tree nodes has been updated
  to handle this bulk load scenario, to ensure B+ tree cache list
  nodes used for the BAS cache list can be balanced without an
  exception respone being returned on a REMOVE call, when the
  BAS resources are successfully removed from the CICSplex.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  UO05399 UO05400 UO05401

Modules/Macros

• EYU0XCX3
  

Fix information

• Fixed component name

  CICS TS Z/OS V6

• Fixed component ID

  5655YA100

Applicable component levels

• R40M PSY UO05401

     UP25/10/21 P F510

• R50M PSY UO05400

     UP25/10/22 P F510

• R60M PSY UO05399

     UP25/10/21 P F510

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.