APAR status
Closed as program error.
Error description
Error Message: Some applications showed a 10-30% regression compared with earlier Java releases. Verbose log shows compilationExcessiveComplexity failure on some of the hottest methods. . Stack Trace: N/A . This regression is possible on all platforms (X86, Power, System z), mostly on power and z
Local fix
This issue can be worked around using the -Xjit:acceptHugeMethods option. Note this would increase the memory usage of the Java program as larger methods would be compiled. The option can be applied to individual methods if preferred.
Problem summary
The compilations of some hottest methods with nested loops failed and the Java program ends up running with less optimized version of these methods. This happens because an incorrect loop related optimization creates too many loops and the number of loops exceeds the limit for some compiled methods.
Problem conclusion
The loop related optimization in JIT has been fixed so that the number of loops created for the hottest methods won't exceed the limit. . This APAR will be fixed in the following Java Releases: 8 SR2 (8.0.2.0) . 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
IV78208
Reported component name
JIT
Reported component ID
620700124
Reported release
130
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2015-10-20
Closed date
2015-10-20
Last modified date
2015-10-20
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
R130 PSY
UP
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Document Information
Modified date:
20 October 2015