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PM47994: db_server loops in usercount() and consumes system resources

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APAR status

  • Closed as program error.

Error description

  • db_server loops in usercount() and consumes system resources
    
    
    Solaris 10
    
    
    ClearCase 7.x, 7.1.x, 7.1.2.x
    
    
    Description of Problem:
    
    Intermittently, a single VOB will become unresponsive:  During
    the single VOB outage event, the performance within the rest of
    the VOB?s hosted on a server will be impacted.  prstat output
    will show that a single db_server process is consuming the CPU
    resources within the userspace.  When issuing a pstack on the
    offending process, the following backtrace is noted:
    
    usercount(0x77638, 0x0, 0xe8, 0x0, 0x0, 0x77c18), at 0x77cfc
    logout_user(0x2, 0x12, 0x0, 0xfece0000, 0x91630, 0x9c1d4), at
    0x77638
    l_closeuser(0x2, 0x1c00, 0xfeec3800, 0x0, 0xff132a00, 0x91630),
    at 0x7456c
    lmc_logout(0x2, 0x800, 0x9c4, 0x3000, 0x91630, 0x9ac7c), at
    0x739a0
    termses(0xffffffff, 0xad4, 0x9c576, 0x9cfac, 0x6, 0x91630), at
    0x59e64
    dt_close(0x7, 0x1, 0xff33fa8c, 0x9a7a8, 0x9452c, 0x91630), at
    0x59880
    db__ctrl_close_db(0xfbc68, 0xff0fa690, 0x1, 0xff0f859c, 0x7a8,
    0x400), at 0xff2dfa3c
    db_close_db(0xfbc68, 0x0, 0xffffffff, 0x8c, 0x14, 0xff33fa8c),
    at 0xff28a180
    db_close_db_V3(0xffbfdd04, 0xffbfdccc, 0xa05d8, 0xfffffff8, 0x1,
    0x0), at 0x2cd18
    dbrpc_3(0xffbfde78, 0xa05d8, 0xff124df4, 0x352f0, 0x91630,
    0x942b4), at 0x2caa8
    dbrpc_3_wrap(0xffbfde78, 0xa05d8, 0x3c, 0xa05d8, 0x91630, 0x0),
    at 0x26908
    ks_svc_getreqset(0xe671c, 0xa05d8, 0x1, 0xff125664, 0xffbfde98,
    0xff0f859c), at 0xff0dd8e8
    client_rpc(0xe6718, 0x0, 0x0, 0xff12562c, 0xff125628, 0xe6f14),
    at 0x26e8c
    rt_wait(0x9c448, 0x0, 0x1, 0xff124428, 0xff0fa6a4, 0x0), at
    0xff0bb094
    rt_run(0xff0fa69c, 0x4e5d2dab, 0x0, 0xf3fd7, 0xff124438, 0x0),
    at 0xff0bb800
    main(0x0, 0x400, 0xc00, 0x800, 0x0, 0x94670), at 0x27bd0
    
    
    Workaround:  None
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    db_server loops in usercount() and consumes system resources
    
    
    Solaris 10
    
    
    ClearCase 7.x, 7.1.x, 7.1.2.x
    
    
    Description of Problem:
    
    Intermittently, a single VOB will become unresponsive:
    During the single VOB outage event, the performance within
    the rest of the VOB?s hosted on a server will be impacted.
    prstat output will show that a single db_server process is
    consuming the CPU resources within the userspace.  When
    issuing a pstack on the offending process, the following
    backtrace is noted:
    
    usercount(0x77638, 0x0, 0xe8, 0x0, 0x0, 0x77c18), at 0x77cfc
    
    logout_user(0x2, 0x12, 0x0, 0xfece0000, 0x91630, 0x9c1d4),
    at 0x77638
    l_closeuser(0x2, 0x1c00, 0xfeec3800, 0x0, 0xff132a00,
    0x91630), at 0x7456c
    lmc_logout(0x2, 0x800, 0x9c4, 0x3000, 0x91630, 0x9ac7c), at
    0x739a0
    termses(0xffffffff, 0xad4, 0x9c576, 0x9cfac, 0x6, 0x91630),
    at 0x59e64
    dt_close(0x7, 0x1, 0xff33fa8c, 0x9a7a8, 0x9452c, 0x91630),
    at 0x59880
    db__ctrl_close_db(0xfbc68, 0xff0fa690, 0x1, 0xff0f859c,
    0x7a8, 0x400), at 0xff2dfa3c
    db_close_db(0xfbc68, 0x0, 0xffffffff, 0x8c, 0x14,
    0xff33fa8c), at 0xff28a180
    db_close_db_V3(0xffbfdd04, 0xffbfdccc, 0xa05d8, 0xfffffff8,
    0x1, 0x0), at 0x2cd18
    dbrpc_3(0xffbfde78, 0xa05d8, 0xff124df4, 0x352f0, 0x91630,
    0x942b4), at 0x2caa8
    dbrpc_3_wrap(0xffbfde78, 0xa05d8, 0x3c, 0xa05d8, 0x91630,
    0x0), at 0x26908
    ks_svc_getreqset(0xe671c, 0xa05d8, 0x1, 0xff125664,
    0xffbfde98, 0xff0f859c), at 0xff0dd8e8
    client_rpc(0xe6718, 0x0, 0x0, 0xff12562c, 0xff125628,
    0xe6f14), at 0x26e8c
    rt_wait(0x9c448, 0x0, 0x1, 0xff124428, 0xff0fa6a4, 0x0), at
    0xff0bb094
    rt_run(0xff0fa69c, 0x4e5d2dab, 0x0, 0xf3fd7, 0xff124438,
    0x0), at 0xff0bb800
    main(0x0, 0x400, 0xc00, 0x800, 0x0, 0x94670), at 0x27bd0
    
    
    Workaround:  None
    

Problem conclusion

  • A fix is available in ClearCase versions 7.1.1.8, 7.1.2.5
    and 8.0.0.1
    

Temporary fix

Comments

APAR Information

  • APAR number

    PM47994

  • Reported component name

    CLEARCASE UNIX

  • Reported component ID

    5724G2901

  • Reported release

    701

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2011-09-15

  • Closed date

    2011-12-16

  • Last modified date

    2011-12-16

  • 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

    CLEARCASE UNIX

  • Fixed component ID

    5724G2901

Applicable component levels

  • R701 PSN

       UP

[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSSH27","label":"Rational ClearCase"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.0.1","Edition":"","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
16 December 2011