APAR status
Closed as program error.
Error description
Error Message: There is a hang in libj9jit*.so when attempting to reclaim and deallocate runtime assumptions during application execution. . Stack Trace: RuntimeAssumption::dequeueFromListOfAssumptionsForJittedBody() () TR_RuntimeAssumptionTable::reclaimMarkedAssumptionsFromRAT(int) ... . Other failures are also possible, particularly crashes involving walking the iprofiler data linked lists. The problem is long standing but due to recent changes is most commonly seen in 8.0.5.40
Local fix
A 100% work-around is not available, but the frequency of failures can be reduced by setting the following environment variable before starting the JVM TR_forceAggressiveRATCleaning=1
Problem summary
The problem is caused by a double free of JIT persistent memory in a time window between compensating a specific kind of runtime assumption and deallocating it.
Problem conclusion
The JIT has been updated to prevent the double free and thus fix the hang issues. . This APAR will be fixed in the following Java Releases: 8 SR5 FP41 (8.0.5.41) 7 SR10 FP55 (7.0.10.55) 7 R1 SR4 FP55 (7.1.4.55) . Contact your IBM Product's Service Team for these Service Refreshes and Fix Packs. For those running stand-alone, information about the available Service Refreshes and Fix Packs can be found at: https://www.ibm.com/developerworks/java/jdk/
Temporary fix
Comments
APAR Information
APAR number
IJ18838
Reported component name
JIT
Reported component ID
620700124
Reported release
130
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2019-09-04
Closed date
2019-09-04
Last modified date
2020-02-06
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
JIT
Fixed component ID
620700124
Applicable component levels
[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSC9HBA","label":"Just In Time (JIT) Compiler"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"130","Edition":"","Line of Business":{"code":"","label":""}}]
Document Information
Modified date:
06 February 2020