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IV34763: KEEPALIVE PACKETS HAVE ZERO WINDOW SIZE WHEN RFC1323 IS OFF.

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APAR status

  • Closed as program error.

Error description

  • If rfc1323 window scaling is NOT in effect AIX keepalive
packets may have a small or zero window size even when
the
AIX recv-q is empty. This requires the remote side to
send
and process a window probe exchange before resuming
transmission.

Local fix

  • Disable keepalive socket option in application or enable
rfc1323 on both ends of connection.

Problem summary

  • Environment with lowered  keepalive intervals will have
performance impact when rfc1323 scalling is disabled.

If rfc1323 window scaling is NOT in effect AIX keepalive
packets may have a small or zero window size even when
the AIX recv-q is empty. This requires the remote side to
send and process a window probe exchange before resuming
transmission.

Problem conclusion

  • The window size is correctly advertized in all cases
with keep alive packet. This avoids the performance issue
created due to small window advertizement.

Temporary fix

  • 



Comments


    

  • 



APAR Information




    

  • APAR number
    IV34763
    • 

  • Reported component name
    AIX V7.1
    • 

  • Reported component ID
    5765H4000
    • 

  • Reported release
    710
    • 

  • Status
    CLOSED  PER
    • 

  • PE
    NoPE
    • 

  • HIPER
    NoHIPER
    • 

  • Submitted date
    2013-01-15
    • 

  • Closed date
    2013-01-15
    • 

  • Last modified date
    2013-04-25
    • 





    

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

    
IV01302
    

    • 

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

    • 



Fix information


    

  • Fixed component name
    AIX V7.1
    • 

  • Fixed component ID
    5765H4000
    • 



Applicable component levels


    

  • R710  PSY  U854914
       UP13/04/25  I  1000
    • 



PTF to Fileset Mapping








      
              
                            

              

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Document Information


            

            


                        

            Modified date:
            

            25 April 2013
            

            
                      

        


        

        


      

    

  



    

  

  
    
            

          
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