IV64659: PERFORMANCE OVERHEAD IN JAVA.SECURITY.POLICY.IMPLIES

PI28439: Ship JAVA apar IV66110 for WAS V70035 using Java 6

APAR status

• Closed as program error.

Error description

• Error Message: N/A
  .
  Stack Trace: N/A
  .
  The security benchmark test shows performance regression in Java
  6 SR16 FP1 compared to Java 6 SR16. The performance regression
  was observed in all platforms. The Aix platform showed more than
  30% regression. The Windows platform showed 12% regression.
  

Local fix

Problem summary

• In Java 6 implementation,  there is no cache to store the
  PermissionCollection in Policy class. Hence, every call to
  Policy.implies result in getting the Permissions for each of the
  code source in the domain. The additional permission check
  introduced by the recent J9VM security fix (IV62634 ) has
  resulted in additional Policy.implies call and caused the
  performance regression. The same security fix is implemented in
  Java 7  without causing any performance regression as Java 7
  implementation uses a cache to store the permission collections.
  It  get the  Permissions for each of the code source in the
  domain only during the first time and used the cached Permission
  collection from the second time onwards for that domain.
  

Problem conclusion

• The JDK has been updated to introduce a cache (WeakHashMap) in
  Policy class to store the PermissionCollection to avoid getting
  the Permissions for each of the code source in the domain again
  and again.
  .
  This APAR will be fixed in the following Java Releases:
     6    SR16 FP2  (6.0.16.2)
     6 R1 SR8 FP2   (6.1.8.2)
  .
  Contact your IBM Product's Service Team for these Service
  Refreshes and Fix Packs.
  For those running stand-alone, Java maintenance is available
  from:
             https://www.ibm.com/developerworks/java/jdk/
  

Temporary fix

Comments

APAR Information

• 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 CLASS LIBS

• Fixed component ID

  620700130

Applicable component levels

• R600 PSY

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