IJ28404: SESSIONID.HASHCODE GENERATES TOO MANY COLLISIONS

APAR status

• Closed as program error.

Error description

• Error Message: The Server webUI intermittently cannot be reached
  for 1-15 minutes with error message "This site cant be reached".
  .
  Stack Trace: at
  com/ibm/security/util/MemoryCache.get(Cache.java:390(Compiled
  Code))
  at com/ibm/jsse2/Y.getSession(Y.java:61(Compiled Code))
  at com/ibm/jsse2/Y.a(Y.java:20(Compiled Code))
  at com/ibm/jsse2/F.a(F.java:186(Compiled Code))
  at com/ibm/jsse2/F.a(F.java:922(Compiled Code))
  at com/ibm/jsse2/D.r(D.java:444(Compiled Code))
  at com/ibm/jsse2/D$b.a(D$b.java:2(Compiled Code))
  at com/ibm/jsse2/D$b.run(D$b.java:3(Compiled Code))
  at
  java/security/AccessController.doPrivileged(AccessController.jav
  a:739)
  at com/ibm/jsse2/D$c.run(D$c.java:12(Compiled Code))
  at
  org/apache/tomcat/util/net/SecureNioChannel.tasks(SecureNioChann
  el.java:423(Compiled Code))
  at
  org/apache/tomcat/util/net/SecureNioChannel.handshakeUnwrap(Secu
  reNioChannel.java:483(Compiled Code))
  at
  org/apache/tomcat/util/net/SecureNioChannel.handshake(SecureNioC
  hannel.java:238(Compiled Code))
  at
  org/apache/tomcat/util/net/NioEndpoint$SocketProcessor.doRun(Nio
  Endpoint.java:1475(Compiled Code))
  at
  org/apache/tomcat/util/net/SocketProcessorBase.run(SocketProcess
  orBase.java:49(Compiled Code))
  at
  java/util/concurrent/ThreadPoolExecutor.runWorker(ThreadPoolExec
  utor.java:1160(Compiled Code))
  at
  java/util/concurrent/ThreadPoolExecutor$Worker.run(ThreadPoolExe
  cutor.java:635)
  at
  org/apache/tomcat/util/threads/TaskThread$WrappingRunnable.run(T
  askThread.java:61)
  at java/lang/Thread.run(Thread.java:812)
  .
  N/A
  

Local fix

• N/A
  

Problem summary

• This is Oracle bug id JDK-8203190
  The implementation of hashCode() in SessionId generates many
  collisions.
  The MemoryCache class is synchronized and because the HashMap
  gets really inefficient, many threads were blocked waiting for
  this class.
  

Problem conclusion

• Better implementation of the hashCode.
  The affected jar is "ibmjsseprovider2.jar"
  The associated Hursley RTC Problem Report is 144312
  The associated Austin Git issue is  #101
  The associated Austin APAR is IJ27807
  JVMs affected: Java 7
  The fix was delivered for Java 7  SR10FP75  and JAVA7.1  SR4FP75
  The build level of this jar for the affected releases is  7.0
  build_20200922--146
  .
  This APAR will be fixed in the following Java Releases:
     7    SR10 FP75 (7.0.10.75)
     7 R1 SR4 FP75  (7.1.4.75)
  .
  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

  SECURITY

• Fixed component ID

  620700125

Applicable component levels