PH39269: DFHDS0102 MESSAGE IS ISSUED INCONSISTENTLY EVEN WHEN QR TCB CPU / DISPATCH RATIO IS CONSISTENTLY ABOVE 5 P 21/09/30 PTF PECHANGE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• When using INITPARM=(DFHQRCPU='01') and while the QR TCB CPU /
  dispatch ratio is consistently over 5%, the DFHDS0102 message
  is not issued every minute as expected. It skips some minutes.
  Here is an example:
  
  DFHDS0102 I 23/07/2021 02:03:20 IYNXK The current QR TCB CPU /
  dispatch ratio is  99.16% and the dispatch / interval ratio is
  65.48%.
  DFHDS0102 I 23/07/2021 02:05:20 IYNXK The current QR TCB CPU /
  dispatch ratio is  99.07% and the dispatch / interval ratio is
  65.24%.
  DFHDS0102 I 23/07/2021 02:07:21 IYNXK The current QR TCB CPU /
  dispatch ratio is  99.07% and the dispatch / interval ratio is
  65.08%.
  DFHDS0102 I 23/07/2021 02:09:21 IYNXK The current QR TCB CPU /
  dispatch ratio is  99.23% and the dispatch / interval ratio is
  65.66%.
  
  Also, in the DFHDS0102 message that immediately follows a
  statistics reset, the dispatch / interval ratio is incorrect. It
  seems to be calculating the interval time based on the time of
  the prior DFHDS0102 rather than based on the time of the reset.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS Users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: Message DFHDS0102 is issued             *
  *                      inconsistently and not every time an    *
  *                      interval expires.                       *
  ****************************************************************
  * RECOMMENDATION: None                                         *
  ****************************************************************
  Message DFHDS0102 is issued inconsistently and not every time an
  interval expires. In addition, the CPU dispatch ratio may be
  incorrect following a stats reset. It is also possible for a
  program check to occur for the TCP task if TCP and CQRC happen
  to interleave while both are using the register save area in the
  CSA.
  

Problem conclusion

• Code has been added to ensure that the messages is issued
  consistenty and correctly. In addition, the message text has
  been edited to fit on one line of console output.
  
  The CICS Transaction Server Messages and Codes have been
  updated as follows
  
  Message DFHDS0102 has been changed to read
  DFHDS0102 date time applid QR TCB CPU / dispatch ratio: nn.nn%.
  QR TCB dispatch / interval ratio: nn.nn%.
  
  Explanation
  The ratio (expressed as a percentage) of the accumulated CPU
  time to the accumulated dispatch time for the QR TCB and also
  the dispatch / interval ratio of the QR TCB. Subject to being
  reset, these numbers provide the average utilization and the
  average saturation of the QR TCB for the current interval.
  If the message states that the CICS statistics have been reset,
  the ratios will not be a true reflection for the current
  interval.
  
  SystemAction
  Processing continues. The suspend interval uses the default
  value of 5 minutes.
  
  User Response
  The ratios are dependent on the CICS workload and machine
  utilization for the current interval and are for information
  only.
  Note that this message is not issued if the dispatch / interval
  ratio for the current interval is less than 5 percent.
  See <xref keyref="explaining.the.qr.tcb.ratio"/> for advice on
  how to interpret these ratios.
  This message is issued, by default, every 5 minutes. To change
  the frequency of this message specify system initialization
  parameter INITPARM=(DFHQRCPU='nn') as a system initialization
  parameter where 'nn' is a number between 01 and 59 minutes. The
  message can be suppressed by specifying a value of '00'.
  
  Module
  DFHQRCPU
  

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:

  UI77391

Modules/Macros

• DFHMEDSC DFHMEDSE DFHMEDSK DFHQRCPU
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R300 PSY UI77391

     UP21/10/01 P F109 ­

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.