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IV57799: CRASH IN CACHEOBJECTMONITORFORLOOKUP

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Error Message: SIGSEV/GPF is received with:#13
0x00007f6acb3e8d43 in cacheObjectMonitorForLookup#14
0x00007f6ac9838fb0 in jitMonitorEntryon stack
.
Stack Trace: ...#12 <signal handler called>#13
0x00007f6acb3e8d43 in cacheObjectMonitorForLookup#14
0x00007f6ac9838fb0 in jitMonitorEntry
.
This can also be manifested as java objects appearing to have
different hashcodes depending on when you call Object.hashcode()

Local fix

  • Specify a fixed nursery size using -Xmn to prevent the nursery
from expanding/contracting

Problem summary

  • Object hashing algorithm can be broken if tenure expands into
where nursery contracts from.Since we use hashing internally for
monitors, this can manifest as a crash in
cacheObjectMonitorForLookup

Problem conclusion

  • This APAR will be fixed in the following Java Releases:
   7 R1 SR1       (7.1.1.0)
.
JVM has been updated to prevent crash from occuring.

Temporary fix

  • 



Comments


    

  • 



APAR Information




    

  • APAR number
    IV57799
    • 

  • Reported component name
    J9 COMMON CODE
    • 

  • Reported component ID
    620700127
    • 

  • Reported release
    270
    • 

  • Status
    CLOSED  PER
    • 

  • PE
    NoPE
    • 

  • HIPER
    NoHIPER
    • 

  • Special Attention
    NoSpecatt
    • 

  • Submitted date
    2014-03-27
    • 

  • Closed date
    2014-04-06
    • 

  • Last modified date
    2014-04-06
    • 





    

  • 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
    J9 COMMON CODE
    • 

  • Fixed component ID
    620700127
    • 



Applicable component levels


    

  • R270  PSY
       UP
    • 








      
              
                            

              

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Document Information


            

            


                        

            Modified date:
            

            21 February 2022
            

            
                      

        


        

        


      

    

  



    

  

  
    
            

          
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