PM04902: TASKS GETTING STUCK IN RZRSTRIG WAITS DUE TO PASSING DATA ON AN IMPORT_ALL REQUEST FOR A LENGTH OF 32767 + 4 BYTES.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• This problem occurs when the data being returned from an AOR is
  a multiple of 32767 + 4.  When the data is this size the 32767
  bytes of data get sent in the TIOA.  The data up to the end of
  the last full TIOA is enough to satisfy the IMPORT_ALL call made
  in the TOR.  By the length of data available exactly matching
  the available data, DFHAPTC returns LAST(YES) to the
  receive_reply routine in RZ domain.
  .
  Upon seeing LAST(YES) the RZ code believes that it has received
  everything.  When it gets called again by DFHPIPM to receive the
  4 byte trailer data it assumes that a new reply is being
  received to waits on RZRSTRIG for new data to arrive.
  .
  Meanwhile the AOR is waiting on IRLINK for the TOR to
  acknowledge receipt of the last TIOA and request the final 4
  bytes.
  .
  Additional Symptom(s) Search Keyword(s):
  KIXREVrer
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: A webservice task gets stuck on an      *
  *                      RZRSTRIG suspend in a TOR while the     *
  *                      partner task in the AOR is stuck on an  *
  *                      IRLINK suspend.                         *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  A webservice request is received by a front-end CICS region
  (TOR). This executes under the control of the webservice
  pipeline. A service handler requests a context switch onto a
  different TRANSACTION ID. This ID is defined as remote so CICS
  uses REQUESTSTREAMS to propagate the webservice request to a
  back-end CICS (AOR).
  The AOR generates a webservice response which is passed back to
  the TOR in a channel. A 4-byte trailer is also sent back which
  follows the channel response.
  DFHPIPM receives the channel using REQUESTSTREAMS. The total
  length of data being returned is X'20000'. This is received by
  DFHAPTC - the REQUESTSTREAMS TC transport module. It is received
  in X'7FFF' chunks. The channel data makes up precisely 4
  X'7FFF' byte chunks. When the last section of the channel is
  received DFHAPTC detects that the X'7FFF' byte TIOA is now empty
  so returns LAST(YES). The REQUESTSTREAM state is therefore
  changed from inbound to outbound.
  DFHPIPM now calls REQUESTSTREAMS to receive the final 4-byte
  trailer which is still in the AOR. However, as the REQUESTSTREAM
  state is no longer inbound, the task suspends on RZRSTRIG -
  waiting to be triggered by the AOR.
  The AOR task is suspended on IRLINK - waiting for the TOR to
  receive the last 4-bytes of data.
  
  ADDITIONAL KEYWORDS :- MRO IRC
  

Problem conclusion

• DFHPIPM has been changed to pass a LAST(NO) indicator when
  importing the channel which contains the webservice response.
  This notifies REQUESTSTREAMS that the imported channel is not
  the last block of data to be received. This stops REQUESTSTREAMS
  from switching the state to outbound during channel import.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

APAR Information

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

  PK73770

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

  UK54235

Modules/Macros

•    DESAPCR  DESPIIS  DESPIPM  DESRZRS  DESRZST
  DESRZTR  DFHAPCR  DFHAPCRA DFHAPCRM DFHAPCRT DFHAPCR1 DFHPIISC
  DFHPIISI DFHPIPM  DFHRZRMC DFHRZRMD DFHRZRSC DFHRZRSD DFHRZRS1
  DFHRZSO  DFHRZSOA DFHRZSOJ DFHRZSOM DFHRZSOT DFHRZSOV DFHRZSO1
  DFHRZTA  DFHRZTAA DFHRZTAM DFHRZTAT DFHRZTRC DFHRZTRD DFHRZTR1
  

Fix information

• Fixed component name

  CICSTS V3 Z/OS

• Fixed component ID

  5655M1500

Applicable component levels

• R400 PSY UK54235

     UP10/02/17 P F002

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.