IV98370: PERFORMANCE DEGRADATION WHILE LOADING CLASSES USING JAVA.NET.URLCLASSLOADER AFTER MIGRATING TO IBM JDK 7 AND ABOVE

APAR status

• Closed as program error.

Error description

• Error Message: Performance degradation after migrating to Java 7
  and above.
  .
  Stack Trace: N/A
  .
  

Local fix

Problem summary

• The problem is caused when classes are loaded using
  java.net.URLClassLoader which use sun.misc.URLClassPath where
  cache is disabled that results in jar files being opened/closed
  large number of times.
  

Problem conclusion

• The JVM has been modified to avoid closing/opening jar files on
  classpath multiple times.
  .
  This APAR will be fixed in the following Java Releases:
     7    SR10 FP10 (7.0.10.10)
     7 R1 SR4 FP10  (7.1.4.10)
     8    SR4 FP10  (8.0.4.10)
  .
  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 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

• R700 PSY

     UP

• R800 PSY

     UP