tunefstab(4)                                                   tunefstab(4)




 NAME    [Toc]    [Back]
      tunefstab - VxFS file system tuning parameters table

 DESCRIPTION    [Toc]    [Back]
      The tunefstab file contains tuning parameters for VxFS file systems.
      tunefs sets the tuning parameters for mounted file systems by
      processing command line options or by reading parameters in the
      tunefstab file.

      Each entry in tunefstab is a line of fields in one of the following
      formats:

           block-device           tunefs-options
           system-default         tunefs-options

      block-device is the name of the device on which the file system is
      mounted.  If there is more than one line that specifies options for a
      device, each line is processed and the options are set in order.

      In place of block-device, system-default specifies tunables for each
      device to process.  If there is an entry for both a block-device and
      system-default, the system-default value takes precedence.

      Lines in tunefstab that start with the pound (#) character are treated
      as comments and ignored.

      The tunefs-options correspond to the tunable parameters that vxtunefs
      and mount_vxfs set on the file system.  Each option in this list is a
      name=value pair. Separate the options by commas, with no spaces or
      tabs between the options and commas.

      See the vxtunefs(1M) manual page for a description of the supported
      options.

 EXAMPLES    [Toc]    [Back]
      If you have a four column striped volume, /dev/vx/dsk/datadb/db03,
      with a stripe unit size of 128 kilobytes per disk, set the
      read_pref_io and read_nstream parameters 128 and four, respectively.
      You can do this in two ways:

           /dev/vx/dsk/datadg/db03 read_pref_io=128k,read_nstream=4

      or:

           /dev/vx/dsk/datadg/db03 read_pref_io=128k
           /dev/vx/dsk/datadg/db03 read_nstream=4

      To set the discovered direct I/O size lower so that it is always lower
      than the default, add the following line to the /etc/vx/tunefstab
      file:




 Hewlett-Packard Company            - 1 -   HP-UX 11i Version 2: August 2003






 tunefstab(4)                                                   tunefstab(4)




           /dev/dsk/c3t1d0 discovered_direct_iosz=128K

 FILES    [Toc]    [Back]
      /etc/vx/tunefstab             Default tunefstab file.

 SEE ALSO    [Toc]    [Back]
      mkfs_vxfs(1M), mount(1M), vxtunefs(1M).

      VERITAS File System Administrator's Guide.


 Hewlett-Packard Company            - 2 -   HP-UX 11i Version 2: August 2003