APAR status
Closed as program error.
Error description
Error Message: An illegal instruction exception (SIGILL) is raised in __arrayTranslateTRTO255() when it is called from a JIT-compiled method. . Stack Trace: __arrayTranslateTRTO255() . The problem can only occur on Java 6.0.1 and Java 7, and only when running on AIX on a POWER7 processor. (This problem does not affect Linux.) The OS setting for "allow_vmx" must be set to "0" for this problem to occur. To view the setting: schedo -o allow_vmx
Local fix
There are two ways to work around this issue: (1) Change the setting of "allow_vmx" to "1": schedo -o -p allow_vmx=1 This setting will cause malloc to use 16-byte alignment causing some wasted memory. This setting is the default. (2) Prevent the JIT compiler from using VMX instructions by exporting/setting the following environment variable: TR_noVsxArrayTranslate=1 Setting this environment variable disables the optimized array translate routines which might case a small performance penalty.
Problem summary
Starting with Java 6.0.1 SR3 and Java 7 SR2, the JIT compiler uses VMX instructions to handle some array translation tasks. If the AIX setting "allow_vmx" is set to "0", the use of VMX instructions will cause a SIGILL.
Problem conclusion
This defect will be fixed in: 6.0.1 SR7 7.0.0 SR6 . The JIT has been modified so that it detects when allow_vmx is set to "0" and disables the use of VMX instructions during array translate.
Temporary fix
Comments
APAR Information
APAR number
IV49719
Reported component name
JIT
Reported component ID
620700124
Reported release
260
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2013-09-19
Closed date
2013-09-25
Last modified date
2013-10-22
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
R260 PSY
UP
[{"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":"260","Edition":"","Line of Business":{"code":"","label":""}}]
Document Information
Modified date:
22 October 2013