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  • 1.  How to increase paging space

    Posted Mon September 29, 2008 06:35 AM

    Originally posted by: SystemAdmin


    Hi Gurus,

    There is a one IBM server Model P620 having physical memory 6 GB.It is running as oracle database server with AIX 5.1 OS running.I was facing the error in morning and that time server was not very slow(not able to telnet).Now I am able to telnet the server and find this.See below:
    1. df -k
    ksh: 0403-031 The fork function failed. There is not enough memory available.
    #
    1. ps -ef|grep -i ora
    ksh: 0403-031 The fork function failed. There is not enough memory available.

    Now I came to know that server was very low in paging/swap space at that time.(still 94% paging/swap used)

    #oslevel
    5.1.0.0
    root@ceres df -k
    Filesystem 1024-blocks Free %Used Iused %Iused Mounted on
    /dev/hd4 65536 54100 18% 2294 16% /
    /dev/hd2 2097152 331444 85% 37601 33% /usr
    /dev/hd9var 3014656 901004 71% 829 1% /var
    /dev/hd3 1310720 804724 39% 229 1% /tmp
    /proc - - - - - /proc
    /dev/hd10opt 65536 58740 11% 296 3% /opt
    /dev/lv1 11534336 1393988 88% 40093 12% /usr/local
    /dev/lv0 52428800 6862324 87% 47567 4% /export/disk1
    /dev/lv2 73400320 1809916 98% 1103 1% /export/disk2
    /dev/lv3 52428800 1637152 97% 784 1% /export/disk3

    Here is some useful information:
    #lsps -s
    Total Paging Space Percent Used
    2048MB 94%
    #lsps -a
    Page Space Physical Volume Volume Group Size %Used Active Auto Type
    paging00 hdisk0 rootvg 2048MB 0 no no lv
    hd6 hdisk0 rootvg 2048MB 94 yes yes lv

    #lsvg -l rootvg
    rootvg:
    LV NAME TYPE LPs PPs PVs LV STATE MOUNT POINT
    hd5 boot 1 1 1 closed/syncd N/A
    hd6 paging 32 32 1 open/syncd N/A
    hd8 jfs2log 1 1 1 open/syncd N/A
    hd4 jfs2 1 1 1 open/syncd /
    hd2 jfs2 32 32 1 open/syncd /usr
    hd9var jfs2 46 46 1 open/syncd /var
    hd3 jfs2 20 20 1 open/syncd /tmp
    hd10opt jfs2 1 1 1 open/syncd /opt
    lg_dumplv sysdump 16 16 1 open/syncd N/A
    paging00 paging 32 32 1 closed/syncd N/A
    lv1 jfs2 176 176 1 open/syncd /usr/local
    #lsvg
    rootvg
    vg0
    #lsvg rootvg
    VOLUME GROUP: rootvg VG IDENTIFIER: 000334bf00004c00000001135403a05d
    VG STATE: active PP SIZE: 64 megabyte(s)
    VG PERMISSION: read/write TOTAL PPs: 542 (34688 megabytes)
    MAX LVs: 256 FREE PPs: 184 (11776 megabytes)
    LVs: 11 USED PPs: 358 (22912 megabytes)
    OPEN LVs: 9 QUORUM: 2
    TOTAL PVs: 1 VG DESCRIPTORS: 2
    STALE PVs: 0 STALE PPs: 0
    ACTIVE PVs: 1 AUTO ON: yes
    MAX PPs per PV: 1016 MAX PVs: 32
    LTG size: 128 kilobyte(s) AUTO SYNC: no
    HOT SPARE: no
    Now my questions are:
    1)In my case only one paging space hd6 is active and the another paging00 space is not active. Could you let me know can I enable both space space or not(these are controlled by kernel.)In case I am able to enable it please let me know how I can enable it.
    2)How I can increase swap or paging space in this case.

    Thank you very much in advance

    Regards
    Anshumali
    #AIX-Forum


  • 2.  Re: How to increase paging space

    Posted Mon September 29, 2008 08:54 AM

    Originally posted by: hdkutz


    Hello,
    use
    smitty pgsp
    to change,increase,activate your paging spaces.

    Seems to me, that you are using Oracle on your machine.
    Check for the right tuning params.
    http://www.ibm.com/developerworks/aix/library/au-aixoptimization-memtun1/

    Cheers,
    ku
    #AIX-Forum


  • 3.  Re: How to increase paging space

    Posted Sat October 04, 2008 10:11 AM

    Originally posted by: SystemAdmin


    Hi,
    when in AIX whtever version you create a Swap or paging space, you are asked if you want also to activate it or not. This is because of you can decide toprepare a Paging Space volume and use it later. Anyway, from smit you can activate it immediately. Go to the smit, LVM, Paging Space menu. Select the one you want activate and activate it immediately. The Paging space will become active immediately and the AIX Kernel will be available to use it. One of the parameters you have to spacify is activate it at any reboot, otherwise the system will consider the activate command valid only until next reboot.
    From the same menu, smit, LVM, Paging space, you will be able also to add another paging space with the dimension you consider the better one, or to increase a paging space you are using, also if it is active and in use. If it is better another paging, a new one, or to enlarge one of the lv you are already using depends on the specific situation. Anyway you can do both the actions. Consider that a paging space very very large normally is worst that two smaller èpaging, and that if you need a fast paging you can create one on the SAN also, for AIX can be managed in the same way.
    At the end, with 6 GB of RAM, and a Oracle DB, maybe you need al least 6 Gb of paging ( the rules that wants 1,5 time the RAM in not so valid ) but in your case, maybe it should be better to increase you paging available to kernel and , don't forget to check the document to tune your AIX for Oracle environment.
    Bye
    #AIX-Forum