PK41661: NEW ZPARM TO DISABLE DB2 Z/OS SERVER SQL INTERRUPT SUPPORT (V8 CM & NFM)

Obtain the fix for this APAR.

APAR status

• Closed as new function.

Error description

• DB2DDF DDFL09 DB2DRDA DJ433
  Client applications changes are necessary in order to tolerate
  the SQL Interrupt environment that DB2 z/OS V8 server systems
  now support. As a result, the user is unable to migrate to
  DB2 z/OS V8 until all susceptible client applications can be
  modified to eliminate their exposure.  Since so many client
  applications must be modified, migration to DB2 z/OS V8 may
  be delayed. In order to allow a seamless migration until all
  client applications can be modified, DB2 z/OS V8 will implement
  a new ZPARM value to cripple the DB2 z/OS SQL Interupt support.
  
  Also see APAR PK59385 which provides the function in DB2 V9
  and also ensures that this becomes a permanent addition to DB2.
  
  ********************************
  Additional Symptoms and keywords:
    DSN6FAC SQLINTRP ENABLE DISABLE SQL Interrupt
    SQL0952N SQL952N SQLCODE952N SQLCODE0952N SQLCODE952
    SQLCODE0952
  

Local fix

• AK41661
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All Distributed Data Facility (DDF) users.   *
  ****************************************************************
  * PROBLEM DESCRIPTION: New System Parameter to disable         *
  *                      DDF support of "SQL Interrupt"          *
  *                      processing.                             *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  DB2 z/OS Version 8 introduced DDF support that allows remote
  client systems to interrupt application SQL based on client
  system timeout values. Prior to DB2 z/OS V8, the only
  interruption mechanism available to a remote client system was
  to terminate the connection to the DB2 z/OS server. But this
  mechanism causes the entire DB2 z/OS thread to terminate, and
  thus abort all changes since the prior commit/rollback. This
  mechanism was therefore sometimes too drastic for remote client
  systems to exploit and as a result, "SQL Interrupt" processing
  was introduced in DB2 z/OS V8 to provide a mechanism to
  interrupt only the currently executing SQL, resulting in a
  negative SQLCODE.
  Some customers may have many remote client systems where the
  logic, in many of their applications, does not tolerate the new
  error symptoms that occur as a result of this new SQL Interrupt
  support. This was not a concern when DB2 z/OS V7 server
  subsystems were involved because DB2 z/OS V7 did not support
  the SQL Interrupt mechanics. But when migrating DB2 z/OS V7
  subsystems to V8, customers may experience application failures
  as a result of the missing application error handling logic.
  This in turn may prevent customers from migrating to V8 until
  all of their applications on all of their client systems, can
  be evaluated and modified to tolerate the new execution-time
  symptoms. Since the effort to implement all the necessary
  client system changes could delay DB2 z/OS V8 migration,
  customers require DB2 z/OS assistance to allow them to migrate
  to V8.
  

Problem conclusion

Temporary fix

Comments

• In cases where remote client application behavior may be
  affected by the new DB2 z/OS V8 "SQL Interrupt" support, and
  to allow migration to DB2 z/OS V8 while the remote client
  application logic can be modified to tolerate the new
  behavior, a new DSNZPARM configuration value will be provided
  that will disable DB2 z/OS V8 "SQL Interrupt" support. The
  default value will be to leave the support enabled. Once all
  client systems, and their associated applications, have been
  changed to tolerate the "SQL Interrupt" behavior, the normal
  DB2 z/OS V8 "SQL Interrupt" support behavior can then be
  restored to the default value.
  Because this new DDF oriented DSNZPARM parameter is considered
  to be only temporary in nature, and only intended as a potential
  V8 migration measure while client system application issues are
  being resolved, this new parameter will be supported by the
  DSN6FAC macro service only, and only in V8. However support
  will be provided to allow the value to be changed on-line so
  customers can more easily test their client changes.
  The DSNZPARM DSN6FAC macro service has been changed to provide
  a new SQLINTRP keyword. The function of the keyword will be
  described in the DSN6FAC macro prologue only, and reads as
  follows:
    SQLINTRP - SQL Interrupt processing ENABLEd or DISABLEd.
               Typically never changed except in cases where
               remote client systems experience SQL Interrupt
               oriented failures and a temporary disablement of
               the DB2 SQL Interrupt support is required until
               remote client systems can be modified to tolerate
               the behavior.
               The default is ENABLE.
  

APAR Information

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

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

  UK26033

Modules/Macros

• DSN@ZP   DSNDFAC  DSNDQWPZ DSNLTINT DSNWZP
  DSN6FAC
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• R810 PSY UK26033

     UP07/06/27 P F706

Fix is available

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