PK23436: DEADLOCK IN COM.IBM.WS.CACHE.CACHE CODE AFTER PK14278

PK23436; 6.0.2.9: deadlock in com.ibm.ws.cache.cache code after PK14278
PK25804; 6.0.2.9: after running WebSphere portal server for a couple of hours

APAR status

• Closed as program error.

Error description

• Deadlock in DRS code. PK14278 did not completely resolve
  the deadlock.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: WebSphere Application Server users who use   *
  *                 distributedMap for caching.                  *
  ****************************************************************
  * PROBLEM DESCRIPTION: The deadlock in cache problem still     *
  *                      occurs even though PK14278 is           *
  *                      applied. PK14278 did not completely     *
  *                      resolved the deadlock problem.          *
  *                                                              *
  *                                                              *
  *                                                              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The cache deadlock occurred when using distributedMap clear
  methods in multiple threads of different cache instances.
  
  From native_stdout.log:
  Found one Java-level deadlock:
  =============================
  "WebContainer : 162": waiting to lock monitor 0x000f0eb8
  (object 0xbb4a55d0, a com.ibm.ws.cache.Cache),
    which is held by "WebContainer : 153"
  "WebContainer : 153": waiting to lock monitor 0x044fddb8
  (object 0xbafcd0f8, a com.ibm.ws.cache.Cache),
    which is held by "WebContainer : 162"
  
  "WebContainer : 162": at com.ibm.ws.cache.Cache.trimCache
    (Cache.java:1712) - waiting to lock <0xbb4a55d0>
      (a com.ibm.ws.cache.Cache)
   at com.ibm.ws.cache.BatchUpdateDaemon.wakeUp
      (BatchUpdateDaemon.java:350)
   at com.ibm.ws.cache.BatchUpdateDaemon.cacheCommand_Clear
     (BatchUpdateDaemon.java:113)
   at com.ibm.ws.cache.Cache.clear (Cache.java:1533)
  
  "WebContainer : 153": at com.ibm.ws.cache.Cache.clearLocal
     (Cache.java:1541)
   - waiting to lock <0xbafcd0f8> (a com.ibm.ws.cache.Cache)
   at com.ibm.ws.cache.Cache.batchUpdate (Cache.java:1193)
   at com.ibm.ws.cache.BatchUpdateDaemon.wakeUp
      (BatchUpdateDaemon.java:317)
   at com.ibm.ws.cache.BatchUpdateDaemon.cacheCommand_Clear
    (BatchUpdateDaemon.java:113)
   at com.ibm.ws.cache.Cache.clear
    (Cache.java:1533)
  

Problem conclusion

• This APAR supersedes the APAR PK14278. Two iFixes are
  available for WAS 6.0.2:
  1. Fixpack 3 to 4
  2. Fixpack 5 to 8.
  
  The fix for this APAR is currently targeted for inclusion
  in fixpack 6.0.2.11.
  Please refer to the recommended updates page for delivery
  information:
  http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
  

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:

Modules/Macros

• DYNACACH
  

Fix information

• Fixed component name

  WEBSPH APP SERV

• Fixed component ID

  5724J0800

Applicable component levels

• R60A PSY

     UP

• R60H PSY

     UP

• R60I PSY

     UP

• R60P PSY

     UP

• R60S PSY

     UP

• R60W PSY

     UP

• R60Z PSY

     UP