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PI83587: CICS ENTERS UNRESPONSIVE LOOP RUNNING LIBERTY WORKLOAD

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APAR status

  • Closed as program error.

Error description

  • CICS enters unresponsive loop running intensive MDB workload

Local fix

  • 



Problem summary


    

  • ****************************************************************
* USERS AFFECTED: All                                          *
****************************************************************
* PROBLEM DESCRIPTION: CICS enters an unresponsive loop when   *
*                      running Liberty workloads that are      *
*                      constrained by TCLASSes.                *
****************************************************************
A small window of vulnerability allows a Liberty workload to
resume an uninitialised task token when exiting a TCLASS wait.
This can trigger a CPU loop while holding the global XMLOCK,
and that can cause an escalation of further problems,
potentially freezing the region.

    



Problem conclusion


    

  • A sequencing error is corrected in DFHXMSH to ensure that
the relevant token is populated before the Resume can be
issued.

    



Temporary fix


    

  • 



Comments


    

  • 



APAR Information




    

  • APAR number
    PI83587
    • 

  • Reported component name
    CICS TS Z/OS V5
    • 

  • Reported component ID
    5655Y0400
    • 

  • Reported release
    000
    • 

  • Status
    CLOSED  PER
    • 

  • PE
    NoPE
    • 

  • HIPER
    YesHIPER
    • 

  • Special Attention
    NoSpecatt / Xsystem
    • 

  • Submitted date
    2017-06-26
    • 

  • Closed date
    2017-11-29
    • 

  • Last modified date
    2018-01-03
    • 





    

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

    • 

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

    
UI52243 UI52244
    

    • 



Modules/Macros


    

  • DFHXMAT

    



Fix information


    

  • Fixed component name
    CICS TS Z/OS V5
    • 

  • Fixed component ID
    5655Y0400
    • 



Applicable component levels


    

  • R000  PSY  UI52243
       UP17/12/02  P  F712  ¢
    • 

  • R100  PSY  UI52244
       UP17/12/01  P  F711  ¢
    • 



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.
    








      
              
                            

              

              [{"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SSGMGV","label":"CICS Transaction Server"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"5.3","Edition":"","Line of Business":{"code":"LOB35","label":"Mainframe SW"}},{"Business Unit":{"code":"BU054","label":"Systems w\/TPS"},"Product":{"code":"SG19M","label":"APARs - z\/OS environment"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"5.3","Edition":"","Line of Business":{"code":"","label":""}}]
              

                          

          
 
        

      

    

      

        

          

            
Document Information


            

            


                        

            Modified date:
            

            03 January 2018
            

            
                      

        


        

        


      

    

  



    

  

  
    
            

          
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