PM99789: The extremeMemory (XM) and disk overflow values retrieved from a map might be different from the original values.

APAR status

• Closed as program error.

Error description

• When disk overflow is enabled using eXtremeMemory, a value
  retrieved from a map might not match the original value that
  was inserted into the map. This error happens only when
  retrieving values that have overflowed to disk. This race
  condition rarely occurs. However, if it does happen, it can
  lead to several unexpected failures such as data loss on
  failover or the exception, OptimisticCollisionException.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  User who enable disk overflow with          *
  *                  eXtremeMemory.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: With XM and disk overflow enabled,      *
  *                      values retrieved from a map might be    *
  *                      be different from the original ones     *
  *                      inserted into map.                      *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When disk overflow is enabled using eXtremeMemory, a value
  retrieved from a map might not match the original value that
  was inserted into the map.  This error happens only for values
  that have overflowed to disk.  This race condition rarely
  happens. However, if it does occur, it can lead to several
  unexpected failures, such as data loss on failover or the
  exception, OptimisticCollisionException.
  

Problem conclusion

• This condition has been addressed to ensure that values
  returned from a map match the values that were inserted.
  

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

  WS EXTREME SCAL

• Fixed component ID

  5724X6702

Applicable component levels

• R860 PSY

     UP