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PK96881: SLOW LEAK IN HEAP POOL 1, FIRST WORD IS 0X00000007

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Customer observes a slow leak in his WebSphere controller
    region.
    
    It was found that there is a storage leak in the security code
    when there is an exception while handling a message in context
    CSIv2 message.
    
    The controller region was run for a length of time with the LE
    Runtime Options HEAPCHK(ON,,,,10),HEAPPOOLS(ON)
    
    Analysis of the resulting Heap Pool Trace for Heap Pool 1 showed
    two instances of Heap Pool 1 elements getting allocated and not
    freed, that had 0x00000007 in the first word:
    ================================================================
    Timestamp: 2009/09/03           14:32:28.878538
    Type: GET   Cell Address: 30C0F220  Cpuid: 02  Tcb: 007BBE88
    CALL NAME                           CALL ADDRESS       CALL
                                                           OFFSET
    CredBucket::getCredential(CredKey*,CredType)
                                        1E2C1EB0           000003BE
    CSIv2MIC(ORB_Request*,CredKey*)     1E2887B0           000000AA
    SecurityManager::receiveInbound(ORB_Request*)
                                        1E289798           0000575A
    ORB_Request::call_inbound_request_interceptors(unsigned
    char,unsigned char)
                                        1EA681A8           0000005A
    ORB_Request::process_inbound_request(acrwObj*,GIOP_Message*)
                                        1EA687B0           00000298
    ORB_Request::comm_inbound_request(acrwObj*)
                                        1EA66758           00000F24
    ACR_ExecutionThread::ProcessInboundRequest(acrwObj*,ThreadCleanU
    p*,BOSS_Object_Key&,Interna...
                                        1EAFB200           000001B8
    ACR_ExecutionThread::RemoveAndProcessWork(ThreadCleanUp*)
                                        1EB0A848           000006EA
    ACR_ExecutionRoutine                1EB0C5C0           0000052A
    CEEVROND                            06BB9898           00000000
    
    ================================================================
    Timestamp: 2009/09/03           14:32:28.866843
    Type: GET   Cell Address: 30C10740  Cpuid: 00  Tcb: 007BBE88
    CALL NAME                           CALL ADDRESS       CALL
                                                           OFFSET
    CredBucket::addCredential(CredKey*,CredType,long,void*,long
    long)
                                        1E287790           00000434
    SecurityManager::receiveInbound(ORB_Request*)
                                        1E289798           00019038
    ORB_Request::call_inbound_request_interceptors(unsigned
    char,unsigned char)
                                        1EA681A8           0000005A
    ORB_Request::process_inbound_request(acrwObj*,GIOP_Message*)
                                        1EA687B0           00000298
    ORB_Request::comm_inbound_request(acrwObj*)
                                        1EA66758           00000F24
    ACR_ExecutionThread::ProcessInboundRequest(acrwObj*,ThreadCleanU
    p*,BOSS_Object_Key&,Interna...
                                        1EAFB200           000001B8
    ACR_ExecutionThread::RemoveAndProcessWork(ThreadCleanUp*)
                                        1EB0A848           000006EA
    ACR_ExecutionRoutine                1EB0C5C0           0000052A
    CEEVROND                            06BB9898           00000000
    
    In an other instance of the problem, we saw the Control region
    run out of native memory and the held storage elements looked
    like below.
    
    Heappools are: ON
    HP# ElmtSize %Primary PoolSize  PoolMeg   #Pools TotalMeg
    1       24        1   000CCCD0      0.8      132    105.6
    
    ElementSize SizeInHex ElementCnt VirtualMeg
      536870920  20000008          1      512.0
         838864  000CCCD0        132      105.6 ****
        7553032  00734008          6       43.2
       36909616  02333230          1       35.2
         262152  00040008         88       22.0
        8388616  00800008          2       16.0
       16777224  01000008          1       16.0
         150520  00024BF8        106       15.2
             16  00000010     676645       10.3 ****
        9226672  008CC9B0          1        8.8
        3355216  00333250          2        6.4
    
    Reviewing the storage , we found that the instances of Heap Pool
    1 elements getting allocated and not freed, that had 0x00000007
    in the first word.
    
    6E88E6A0 6E616000 000CCCD0 C5E7F3F1  6E7BA9C0 |na..........n{
    6E88E6B0 00000001 00000001 00000007* 00000000 |................
    6E88E6C0 49424D12 00000008 00000000  14200001 |IBM..........
    6E88E6D0 00000001 00000001 00000007* 00000000 |................
    6E88E6E0 00010100 D3D4D9C5 C3404040  00010000 |.........@@@....
    6E88E6F0 00000001 00000001 00000007* 00000000 |................
    6E88E700 53656E64 696E6743 6F6E7465  78742F43 |SendingContext/C
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:  All users of IBM WebSphere Application      *
    *                  Server V6.0.1                               *
    ****************************************************************
    * PROBLEM DESCRIPTION: For WebSphere Application Server for    *
    *                      z/OS, there is a slow memory leak in    *
    *                      the security code. The memory leak      *
    *                      happens in Heap Pool 1 where the        *
    *                      first word of the leaked storage        *
    *                      contents is 0X00000007.                 *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    For WebSphere Application Server for z/OS, there is a memory
    leak in Heap Pool 1. The leak occurs when there is any error
    handling a CSIv2 message in context message for which the
    saved credential is no longer valid. When LE options are
    enabled as follows, HEAPCHK(ON,,,,10),HEAPPOOLS(ON) the trace
    produced is similar to
    
    Timestamp: 2009/09/03           14:32:28.878538
    Type: GET   Cell Address: 30C0F220  Cpuid: 02  Tcb: 007BBE88
    CALL NAME                           CALL ADDRESS       CALL
                                                           OFFSET
    CredBucket::getCredential(CredKey*,CredType)
                                        1E2C1EB0           000003BE
    CSIv2MIC(ORB_Request*,CredKey*)     1E2887B0           000000AA
    SecurityManager::receiveInbound(ORB_Request*)
    
    where it shows that storage is allocated due to the
    getCredential function. This storage is NOT released and its
    contents start with 0X00000007.
    

Problem conclusion

  • The security code was modified to correctly release storage
    allocated even when there is a failure handling CSIv2 message
    in context messages.
    
    APAR PK96881 is currently targeted for inclusion in Service
    Level (Fix Pack) 6.0.2.41 of WebSphere Application Server
    V6.0.1.
    
    Please refer to URL:
    //www.ibm.com/support/docview.wss?rs=404&uid=swg27006970
    for Fix Pack availability.
    

Temporary fix

Comments

APAR Information

  • APAR number

    PK96881

  • Reported component name

    WEBSPHERE FOR Z

  • Reported component ID

    5655I3500

  • Reported release

    601

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2009-09-22

  • Closed date

    2010-01-22

  • Last modified date

    2010-05-04

  • 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 FOR Z

  • Fixed component ID

    5655I3500

Applicable component levels

  • R601 PSY UK55832

       UP10/04/16 P F004

Fix is available

  • Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.

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Document Information

Modified date:
10 February 2022