PH51645: REPEATED JSP RE-COMPILATION AFTER THE MANUAL UPDATE OF THE JSP FILE UNDER HEAVY LOAD

APAR status

• Closed as program error.

Error description

• After manual update of jsp under high load, the jsp file could
  be repeatedly recompiled. If this issue happens, we will see
  SRVE0242I and SRVE0253I repeatedly on the same jsp file. By
  gathering the jsp trace, the compile is triggered because the
  timestamp of the jsp file is different from the cached
  timestamp.
  ```
  com.ibm.ws.jsp.webcontainerext.JspDependent isOutdated
  dependentFile ts [1668993878632] differs from cached ts
  [1668654956886]. Recompile JSP.
  ```
  Once the jsp file is compiled, the both timestamps are supposed
  to have the same value and jsp compile is no longer triggered.
  But if the issue happens, the value is not updated and the jsp
  compile is triggered repeatedly every time the jsp file is
  accessed after the jsp reload interval.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  Users of JavaServer Pages on WebSphere      *
  *                  8.5.5 and 9.0                               *
  ****************************************************************
  * PROBLEM DESCRIPTION: Under high load, the JSP Engine may     *
  *                      repeatedly recompile JSP files          *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  If a JSP is modified, and the application server is under high
  load, the JSP engine may not properly track the timestamps of
  the JSP dependencies and therefore think they are out of date.
  This will cause the JSP engine to translate and compile the
  pages repeatedly.
  This problem will occur when trackDependencies is enabled and
  the the time between re-compilations will depend on the
  reloadInterval setting (default 5 seconds).
  

Problem conclusion

• The code has been updated to avoid the synchronization issue
  that caused this problem.
  
  The fix for this APAR is targeted for WebSphere version
  8.5.5.26, and 9.0.5.19.
  
  
  For more information, see 'Recommended
  Updates for WebSphere Application Server':
  https://www.ibm.com/support/pages/node/715553
  

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

  WEBSPHERE APP S

• Fixed component ID

  5724J0800

Applicable component levels