PH51368: SWITCH CURRENT LOCKS TO SYNCHRONIZED

APAR status

• Closed as program error.

Error description

• The current locking code using
  ReentrantReadWriteLock should be working, but it interacts
  with resource adapters that may result in a dead lock.
  
  Swtiching to use synchronized with an object.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server using connection factories           *
  ****************************************************************
  * PROBLEM DESCRIPTION: A deadlock may occur between a          *
  *                      resource adapter and server             *
  *                      handlelist code.                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  A java core will contain a ReentrantReadWriteLock in the
  HandleList server class and a
  customers resource adapter that is attempting process an
  error with the connection error event. Multiple threads
  sometimes are used to clear failing connections as fast as
  possible.   Its unlikely for most customer to run into this
  problem.
  

Problem conclusion

• The handlelist code was change from using
  ReentrantReadWriteLock to Synchronized methods.
  
  The fix for this APAR is targeted for inclusion in fix pack
  8.5.5.25 and 9.0.5.19. For more information, see 'Recommended
  Updates for WebSphere Application Server':
  https://www.ibm.com/support/pages/node/715553
  

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:

Fix information

• Fixed component name

  WEBSPHERE APP S

• Fixed component ID

  5724J0800

Applicable component levels