During high database activity, many Oracle processes hang or do not respond, and display the following stack trace:

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Article ID: 100024850

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Updated On:

Description

Error Message

 

[ ERROR MESSAGES ]
            odm_rwsleep_lock+0x11c
            odm_iop_get+0xac
            odm_io+0x110
            odm_io_stat+0x12c
            odmioctl+0x104
            vno_ioctl+0xd0
            ioctl+0x11c

Cause

 

Incident Number: 2219488 (2203917)
During high database activity, many Oracle processes hang or do not respond, and display the following stack trace:
There are lots of new processes starting at the same time (new client connections) that trigger a requirement for many new iop’s to be created (one for each new process) and added to the array, this then hinders the current odm i/o workload and causes a bottleneck or odm i/o generally until the iop have been successfully added into the array.
 

Resolution

 

 
[ RESOLUTION ]
 
1.  Here is the details on the patch.
   ----------------------------------------------------------------
    1)  For VxVM6.0 for HPUX11v3.
    The known incident, e2205874 was fix in SF6.0
    The release note SF6.0 below, page 33, the incident 2205874 was fixed in VxFS 6.0 via 2203917. 
     ---------------
     2203917 Peformance problem with Oracle 10g using ODM.
     ---------------

    2) For VxVM5.0MP1 for HPUX11v3.
    This incident fixed in VRTSodm 5.0RP3HF2 for HPUX11v3 initially.
     Later on,  VRTSodm 5.0 GARP4( PHKL_41797 ) was delivered: includes the Incident Number: 2219488 (2203917)
    The information about each process performing an ODM I/O is saved in a table called "odm_iop_table". 
    The processes hang because of the contention to obtain a lock to update this table.
 
    The code is modified to obtain a hash bucket lock instead of a global table lock.
    The number of hash buckets has been increased from 32 to 256 to reduce the contention and avoid the hang.
 
 
 
2. cksum(1) Output:
            ----------------------------------------------------------------
            VRTSodm.ODM-KRN,fr=5.0.31.0,fa=HP-UX_B.11.31_IA,v=Veritas:
            1966787352 699488 /usr/conf/mod/odm
            1893906240 2826 /usr/conf/mod/odm.prep
 
            VRTSodm.ODM-KRN,fr=5.0.31.0,fa=HP-UX_B.11.31_PA,v=Veritas:
            3652244689 794152 /usr/conf/mod/odm
            1893906240 2826 /usr/conf/mod/odm.prep
 
            VRTSodm.ODM-RUN,fr=5.0.31.0,fa=HP-UX_B.11.31_IA,v=Veritas:
            3183747495 3575964 /sbin/fs/odm/mount
            4269797847 3001 /sbin/init.d/odm
            1671848669 82700 /opt/VRTSodm/bin/odmmkfile
 
            VRTSodm.ODM-RUN,fr=5.0.31.0,fa=HP-UX_B.11.31_PA,v=Veritas:
            205971113 1351680 /sbin/fs/odm/mount
            4269797847 3001 /sbin/init.d/odm
            4129963315 49152 /opt/VRTSodm/bin/odmmkfile
 
            VRTSodm.ODM-MAN,fr=5.0.31.0,fa=HP-UX_B.11.31_IA/PA,
                        v=Veritas:
            1304708272 3176 /opt/VRTSodm/man/man1/odmmkfile.1
            ----------------------------------------------------------------
 
3. Supersedes:
            PHKL_38241 PHKL_39130 PHKL_39471
 
 
4. Installation Instructions:
            Please review all instructions and the Hewlett-Packard
            SupportLine User Guide or your Hewlett-Packard support terms
            and conditions for precautions, scope of license,
            restrictions, and, limitation of liability and warranties,
            before installing this patch.
            ------------------------------------------------------------
            1). Back up your system before installing a patch.
 
            2). Login as root.
 
            3). Copy the patch to the /tmp directory.
 
            4). Move to the /tmp directory and unshar the patch:
 
                        cd /tmp
                        sh PHKL_41797
 
            5). Run swinstall to install the patch:
 
                        swinstall -x autoreboot=true -x patch_match_target=true \
                                     -s /tmp/PHKL_41797.depot
 
            By default swinstall will archive the original software in
            /var/adm/sw/save/PHKL_41797. If you do not wish to retain a
            copy of the original software, include the patch_save_files
            option in the swinstall command above:
 
                        -x patch_save_files=false
 
            Warning: If patch_save_files is false when a patch is installed,
                         the patch cannot be deinstalled. Please be careful
                         when using this feature.
 
            For future reference, the contents of the PHKL_41797.text file is
            available in the product readme:
 
                        swlist -l product -a readme -d @ /tmp/PHKL_41797.depot
 
            To put this patch on a magnetic tape and install from the
            tape drive, use the command:
 
                        dd if=/tmp/PHKL_41797.depot of=/dev/rmt/0m bs=2k
 
            Special Installation Instructions: None
 

 


Applies To

 

[ VERSION OF OS/PACKAGE ]
HP-UX Symc-HP B.11.31 U 9000/800 1650003722 unlimited-user license
SFORA5.0.1 for HPUX11v3

Issue/Introduction

 
Oracle is having slow performance when running reports using VRTSvxfs 5.0 MP1P1 and VxVM 5.0RP8 which already include fixes for performance issues.
 
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