APAR status
Closed as program error.
Error description
Error Message: SIGSEV inside JIT compiled code, or in the Garbage Collector. Other types of symptoms are possible like crashing in the the interpreter or unexpected exceptions. . Stack Trace: N/A . For a method to trigger this problem it must be a rather large method (900 or more bytes of bytecodes) and it must have a high concentration of calls.
Local fix
Use the following java command line option to avoid the problem: -Xjit:disableEscapeAnalysis Using this option may have a slight impact on performance, but in most cases it will be less then 1%.
Problem summary
The JIT will incorrectly determine that it's safe to stack allocate an object. The object reference is then leaked into the heap and a crash can occur if the GC encounters this reference, the object is overwritten by future stack usage, or a truncated stack reference is used in a compressed references JVM. It's worth noting that this problem is rare and it is difficult to determine if a given issue is an example of this problem.
Problem conclusion
This defect will be fixed in: 6.0.0 SR8 5.0.0 SR11 FP2 . The JIT was modified so that it will handle this case by correctly determining when objects can not be stack allocated. . To obtain the fix: Install build 20100203 or later
Temporary fix
Comments
APAR Information
APAR number
IZ70114
Reported component name
JAVA 5 JIT
Reported component ID
620500124
Reported release
500
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2010-02-13
Closed date
2010-02-13
Last modified date
2010-04-29
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
JAVA 5 JIT
Fixed component ID
620500124
Applicable component levels
R500 PSN
UP
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Document Information
Modified date:
29 April 2010