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
IZ69974
Reported component name
JIT
Reported component ID
620700124
Reported release
600
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2010-02-12
Closed date
2010-02-12
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
JIT
Fixed component ID
620700124
Applicable component levels
R600 PSN
UP
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Document Information
Modified date:
29 April 2010