stager.cmd(4)

NAME
     stager.cmd - Defines SAM-QFS stager directives

SYNOPSIS
     /etc/opt/SUNWsamfs/stager.cmd

AVAILABILITY
     SUNWsamfs

DESCRIPTION
     Directives for controlling the SAM-QFS stager are read from
     /etc/opt/SUNWsamfs/stager.cmd.  In the stager.cmd file, each
     directive must appear on its own line.  Each directive has
     the following format:

     keyword = value

     Comment lines can appear in the stager.cmd file.  A pound
     sign (#) in column 1 indicates a comment line.

     The stager.cmd file accepts the following directives:

     directio = on|off
               Set the file reading method for staging. The
               directive on will set direct I/O for all staging
               if file size is equal to or greater than
               dio_min_size. off will cause paged I/O to be used.
               The default is on.

               NOTE: Staging on a shared QFS file system always
               uses direct I/O.

     dio_min_size = n
               If the file size is < n megabytes, the stager will
               use paged I/O for non-shared QFS file systems. The
               default is 8 megabytes.  If directio = off all
               stage io is paged.

               NOTE: dio_min_size is ignored for shared QFS file
               systems which always use direct I/O.

     drives = library count
               Sets the number of drives to use for staging on
               media library library to a number specified by
               count.  The default value is the actual number of
               drives in library.

               The library specified must be the family set name
               of a media library as defined in the mcf file.  If
               this directive is specified, the stager uses only
               count number of drives in the media library to
               stage archive copies.  This directive prevents the

               stager from using all drives in a media library
               and possibly interfering with archiving.

               For example, the following directive specifies
               that 3 drives should be used for staging in an
               ADIC/Grau media library.

               drives = gr50 3

     bufsize = media buffer_size [ lock ]
               Sets the stage buffer size for a specific media
               type.

               For media, specify a media type from the mcf(4)
               man page.

               For buffer_size, specify an integer value in the
               range 2 < buffer_size < 8192.  The default is 16.
               The buffer_size specified is multiplied by the
               default block size for media.  For more
               information on default block sizes, see the
               dev_blksize description on the defaults.conf(4)
               man page.

               If lock is specified, the stager locks the stage
               buffer in memory.  If the stage buffer is locked,
               system CPU time can be reduced.

     logfile = filename [event]
               Sets the name of the stager log file to filename,
               specified as an absolute pathname.  By default, no
               log file is written.  event is start, finish,
               cancel, error, or all.  The default is finish,
               cancel, and error.

               The stager log file contains a line for each file
               staged.  The line contains the event type, date,
               time, media, VSN, inode generation number of the
               file, position and offset of where the file is
               stored, name of the file, copy number, user id,
               group id, requestor's user id, equipment number of
               the drive upon which the file was staged, and the
               type of stage, 'V' for data verify and '-' for
               others.

     maxactive = number
               Sets the maximum number of stage requests that can
               be active at one time in the stager to an integer
               number.  The minimum number is 1.  The default
               number is based on memory size, 5000 per gigabyte.
               The maximum number is 500000.

               The number of outstanding stage requests has a
               direct impact on incore inode usage, since each
               request requires an incore inode for the duration
               of the stage.  Sites may wish to increase the
               default number of incore inodes if they greatly
               increase the maximum number of stage requests.
               This can be done by setting ninodes in the
               /etc/system file, as shown in the following
               example.

               set samfs:ninodes=100000

               For more information on ninodes, see the Sun QFS
               File System Configuration and Administration
               Guide.

     maxretries = number
               Sets the maximum number of stage retries attempted
               per archive copy when certain errors are
               encountered to an integer number.  The minimum
               number is 0.  The default number is 3.  The
               maximum number is 20.

     copysel = n1:n2:n3:n4
               Sets the copy selection sequence for staging.  n?
               must be a range of 1 <= n? <= 4. By default,
               1:2:3:4 is defined, so copy number 1, 2, 3 then 4
               is selected for staging if stage is not initiated
               by stage(1) and copy number is not specified by -c
               option.

               Four copies, n1 to n4, must be defined, even if
               there are less than four copies available.

     fs = file_system_family_set_name
               Specifies that the subsequent directives apply to
               the indicated file_system_family_set_name only
               until stream definition is met. File system
               specific directives override general directives.

               NOTE: Currently, only copysel definition can be
               defined for the specific file system.

STREAM DEFINITIONS SECTION
     The streams and endstreams directives delimit this section
     of the stager.cmd file.

     Each line begins with the media type followed by the
     definitions.  The syntax for this line is as follows:

     media definitions

     where:

     media     The media type. Currently, only 'dk' is supported.

     definitions

     -maxsize size
               Set the maximum size of the stream to size. size
               may be specified with the suffixes 'b', 'k', 'M',
               'G', and 'T', for bytes, kilobytes, megabytes,
               gigabytes, and terabytes.  The default unit size
               is bytes.  The default value is 1G bytes.  Files
               to be staged from the same stream will be added to
               the same stream. If size of the stream hit the
               size, new stream will be created for the VSN.

     -maxcount count
               Set the maximum file count to count for the each
               stream.  The default value is 0.  Files to be
               staged from the same VSN will be added to the same
               stream.  If count of the file hit the count, new
               stream will be created for the VSN.

               If more than one of -maxsize or -maxcount are
               specified, the first condition encountered creates
               the new stream for VSN.

EXAMPLES
     The following is an example /etc/opt/SUNWsamfs/stager.cmd
     file:

     logfile = /var/opt/SUNWsamfs/log/stager
     drives= hp30 1
     copysel = 4:3:2:1
     fs = samfs1
     copysel = 3:1:4:2
     streams
     dk -maxsize 2G -maxcount 10000
     endstreams

     The results of the stager's operations are found in
     /var/opt/SUNWsamfs/log/stager.  For the media library
     specified as hp30, the stager is allowed to use only 1 drive
     for staging files.  The stager selects copy number 4, 3, 2
     then 1 for staging files by default.  The stager selects
     copy number 3, 1, 4 then 2 for staging files for the file
     system samfs1.  The size of stream is limited to 2G bytes,
     and the maiximum file count for the each stream is limited
     to 10000 for the media type dk.

FILES
     The following files are used by the stager:

     /etc/opt/SUNWsamfs/stager.cmd Stager command file.

SEE ALSO
     sam-stagerd(1M).

     defaults.conf(4), mcf(4).