2

The following represents the incoming references to a large amount of memory, seen in a primary heapdump file after an OutOfMemoryException in WebSphere 6:

Class Name                                                                    | Shallow Heap | Retained Heap
-------------------------------------------------------------------------------------------------------------
                                                                              |              |
java.util.HashMap$Entry[1048576] @ 0xbd42d00                                  |    4,194,320 |   122,167,192
'- java.util.HashMap @ 0x1044918                                              |           48 |   122,167,240
   '- class com.ibm.ejs.j2c.ConnectorRuntime @ 0x15871128                     |           28 |   122,167,356
      |- org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader @ 0x133fa48 |           96 |       191,140
      |- class com.ibm.ejs.j2c.RALifeCycleManagerImpl @ 0x15834ea0            |           28 |           108
      |- class com.ibm.ejs.j2c.ConnectorRuntime @ 0x15871128                  |           28 |   122,167,356
      |- class com.ibm.ejs.j2c.PoolManager @ 0x158723d8                       |           28 |         2,028
      |- class com.ibm.ejs.j2c.RAWrapperImpl @ 0x15875eb0                     |           28 |         1,612
      |- class com.ibm.ejs.j2c.XMLReader @ 0x15e6ef88                         |           28 |           156
      |- class com.ibm.ejs.j2c.ConnectionFactoryRefBuilderImpl @ 0x15ed5468   |           28 |           140
      |- class com.ibm.ejs.j2c.ConnectionFactoryDetailsImpl @ 0x15efc758      |           28 |       201,060
      |- class com.ibm.ejs.j2c.ResourceAdapterDDImpl @ 0x1605ce60             |           28 |           220
      |- class com.ibm.ejs.j2c.ConnectorPoolProperties @ 0x1605d900           |           28 |           972
      |- class com.ibm.ejs.j2c.ConnectionManager @ 0x163eea78                 |           28 |           196
      |- class com.ibm.ejs.j2c.XATransactionWrapper @ 0x163f0a30              |           28 |            28
      |- class com.ibm.ejs.j2c.ConnectionFactoryBuilderServerImpl @ 0x16431540|           28 |           364
      |- class com.ibm.ejs.j2c.DefaultSecurityHelper @ 0x16434800             |           28 |            28
      |- class com.ibm.ejs.j2c.MCWrapper @ 0x165542a0                         |           28 |           764
      |- class com.ibm.ejs.j2c.PoolManager$GetJ2CProperties @ 0x16577758      |           28 |            28
      |- class com.ibm.ejs.j2c.SharedPool @ 0x16578100                        |           28 |            28
      |- class com.ibm.ejs.j2c.FreePool @ 0x165787f0                          |           28 |            28
      |- class com.ibm.ejs.j2c.CMConfigDataImpl$GetJ2CProperties @ 0x16977b30 |           28 |            28
      '- Total: 19 entries                                                    |              |
-------------------------------------------------------------------------------------------------------------     

I didn't go through them all, but the hashmap entries seemed to all have empty values.

What could be the cause of this? How do I get more information?

  • Hello, I'm experiencing very similar issue with WAS 7.0. Did you manage to solve it? – krtek Jul 11 '12 at 7:50
  • Yes. It was not a memory leak it was simply that the max heap size was too small. – Synesso Jul 12 '12 at 3:41
1

The solution was: Increased max heap size for server from 256 to 768MB. Also enabled garbage collection logging.

0

If you're using Oracle, then the problem might be in Oracle Connection Pool memory consumption.

See this whitepaper, in particular section about setting oracle.jdbc.implicitStatementCacheSize parameter.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.