IBM Support

IT25939: Multi-threaded MQ client application on Windows hangs in MQCONNX

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APAR status

  • Closed as program error.

Error description

  • A multi-threaded MQ application on Windows hangs in MQCONNX.
Before this, it may be observed that another thread has exited
without performing MQCLOSE and MQDISC processing.

A similar problem is observed at version 9.1.0.x and is resolved
by APAR IT28639.

Local fix

  • 1. Ensure that all child threads terminate correctly by closing
MQ resources with MQCLOSE and MQDISC.
2. Set the client channel definition to use SHARECNV(0)

Problem summary

  • ****************************************************************
USERS AFFECTED:
Users of WebSphere MQ on Windows with multi-threaded client
applications.


Platforms affected:
Windows

****************************************************************
PROBLEM DESCRIPTION:
If a child thread in an application terminated abnormally within
an MQDISC, any subsequent threads which were started hung during
the MQCONNX request.

The subsequent MQCONNX request was waiting for the previous
thread which is no longer available.

Problem conclusion

  • The MQ client code for Windows has been changed to recognize
that a child thread has terminated abnormally and no longer
wait.

---------------------------------------------------------------
The fix is targeted for delivery in the following PTFs:

Version    Maintenance Level
v8.0       8.0.0.16
v9.0 LTS   9.0.0.11
v9.1 LTS   9.1.0.3
v9.x CD    9.1.1


The latest available maintenance can be obtained from
'WebSphere MQ Recommended Fixes'
http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037

If the maintenance level is not yet available information on
its planned availability can be found in 'WebSphere MQ
Planned Maintenance Release Dates'
http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
---------------------------------------------------------------

Temporary fix

  • 



Comments


    

  • 



APAR Information




    

  • APAR number
    IT25939
    • 

  • Reported component name
    IBM MQ BASE MP
    • 

  • Reported component ID
    5724H7251
    • 

  • Reported release
    800
    • 

  • Status
    CLOSED  PER
    • 

  • PE
    NoPE
    • 

  • HIPER
    NoHIPER
    • 

  • Special Attention
    NoSpecatt / Xsystem
    • 

  • Submitted date
    2018-08-21
    • 

  • Closed date
    2020-06-18
    • 

  • Last modified date
    2020-06-22
    • 





    

  • 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
    IBM MQ BASE MP
    • 

  • Fixed component ID
    5724H7251
    • 



Applicable component levels


    








      
              
                            

              

              [{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"8.0.0.0","Line of Business":{"code":"LOB45","label":"Automation"}}]
              

                          

          
 
        

      

    

      

        

          

            
Document Information


            

            


                        

            Modified date:
            

            23 June 2020
            

            
                      

        


        

        


      

    

  



    

  

  
    
            

          
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