JR52594: ROUND-ROBIN TASK ASSIGNMENT IS NOT DISTRIBUTING EVENLY

8.5.5.0-WS-BPM-IFJR52594
Version 8.5 Refresh Pack 7 for the IBM Business Process Manager products

APAR status

• Closed as program error.

Error description

• If you model a task assignment by setting the User Distribution
  property to round robin, created tasks are assigned in a
  round-robin way only if they are created one after the other
  with a couple of seconds between when each task is created. If
  tasks are created in parallel or without enough delay between
  when the tasks are created, consecutive tasks are assigned to
  the same user.
  

Local fix

• Ensure that tasks are not created in parallel and there is
  enough time between creating two consecutive tasks. The length
  of this delay depends on the available system resources and
  current workload on the system and might change over the day.
  

Problem summary

• This issue occurs when concurrent threads used for concurrent
  task creations on the same server retrieve the same user
  identity from the database as the last one used by the
  round-robin assignment. As a result, the concurrent threads use
  the same user ID next and assign all concurrently created tasks
  to this same user ID.
  

Problem conclusion

• A fix is available for IBM BPM V8.5.5.0 that provides an
  alternative round-robin procedure that optimizes the selection
  of the next user ID according to the server. Although this fix
  ensures a correct round-robin assignment for tasks created on
  the same server, it does not coordinate the user selection
  between the servers within a cluster.   To activate the
  alternative round-robin procedure, add the following setting to
  the custom configuration in the 100Custom.xml file:
  
  <server>
     <bpd-engine>
        <optimize-round-robin-per-server>true
        </optimize-round-robin-per-server>
     </bpd-engine>
  </server>
  
  When no such setting exists or is set to false, then the
  existing round robin procedure is applied.
  
  On Fix Central (http://www.ibm.com/support/fixcentral), search
  for JR52594:
  
  1. Select IBM Business Process Manager with your edition from
    the product selector, the installed version to the fix pack
    level, and your platform, and then click Continue.
  
  2. Select APAR or SPR, enter JR52594, and click Continue.
  
  When you download fix packages, ensure that you also download
  the readme file for each fix. Review each readme file for
  additional installation instructions and information about the
  fix.
  

Temporary fix

• Not applicable
  

Comments

APAR Information

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

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

Fix information

• Fixed component name

  BPM STANDARD

• Fixed component ID

  5725C9500

Applicable component levels

• R855 PSY

     UP