Filestat

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Description The [filestat] utility is an additional file system specific command that displays the device block allocation information for a file.

The problem this utility is addressing to provide customers with a simple way of finding out how contiguous a file is on a storage device. This is required in situations where sequential file access performance is not as expected and file system clustering does not appear to be reading block sizes from the storage device as expected.

The filestat utility can be used to determine if a file has become fragemented enough to warrant reallocation of the file or rebuilding of the file system itself.

The filestat utility is also used to confirm that the file system allocation parameters chosen with mkfs(1M) are doing what the user expected.

The file system dependant front end is used to provide a similar interface for other file system implementations, should other file system vendors choose to implement the same functionallity. /usr/sbin/filestat is a hard link to /usr/sbin/clri in the same way as ff, fsck, mount etc and calls the /usr/lib/fs//filestat executable.

The output of the ufs specific filestat command is:

# filestat /home/rmc/bigfile

Inodes per cyl group:       64
Inodes per block:           64
Cylinder Group no:          0
Cylinder Group blk:         64
File System Block Size:     8192
Device block size:          512
Number of device blocks:    204928

Start Block    End Block    Length (Device Blocks)
-----------    -----------  ----------------------
      66272 -> 66463        192
      66480 -> 99247        32768
    1155904 -> 1188671      32768
    1277392 -> 1310159      32768
    1387552 -> 1420319      32768
    1497712 -> 1530479      32768
    1607872 -> 1640639      32768
    1718016 -> 1725999      7984
    1155872 -> 1155887      16

Number of extents:          9
Average extent size:        22769 Blocks

Maintenance Commands                                 filestat(1M)

NAME
     filestat - print inode block allocation

SYNOPSIS
     filestat  filename

DESCRIPTION
     filestat  prints the  file  system device  block  allocation
     for the specified file. 

     Read and write permission is required on the specified  file
     system device on which the file resides. 

     The fileblocks utility  is useful to  determine the physical
     layout of a file on the storage device, and for  determining
     if the file has become fragmented over time.

     fileblocks is a symbolic link to clri .

OPTIONS
     -F FSType Specify the  FSType on which to operate.  The
                FSType should either  be  specified  here  or  be
               determinable  from   /etc/vfstab by matching  spe-
               cial with an entry in the table, or by  consulting
               /etc/default/fs.

     -V        Echo the complete command line, but do not execute
               the  command.  The  command  line  is generated by
               using the options and arguments  provided  by  the
               user  and  adding to them information derived from
               /etc/vfstab. This option should be used to  verify
               and validate the command line.

FILES
     /etc/default/fs
               default local file system type

     /etc/vfstab
               list of default parameters for each file system

ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:
     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Availability                | SUNWcsu                     |
    |_____________________________|_____________________________|

SEE ALSO
     filestat_ufs(1M), vfstab(4), attributes(5)

NOTES
     This command may not be supported for all FSTypes.

Maintenance Commands                             filestat_ufs(1M)

NAME
     filestat_ufs - print inode block allocation

SYNOPSIS
     filestat  filename(s)

DESCRIPTION
     The ufs-specific module of  fileblocks dumps the ufs  device 
     block allocation for  the specified  file residing on  a ufs
     file system.

     The special  device  is  looked  up  from  the  mount  table
     /etc/mnttab and opened. Read permission  is required  on the
     special file for the file system holding the file.

     All  block  addresses  are  printed in device block numbers, 
     which default to 512 bytes unless otherwise printed.

     A  summary  of  the  files  inode  location  information  is 
     printed,  including  the device block number of the cylinder
     group number which the inode resides in and the device block
     number for the cylinder group. 

     The  device  block  address range for each sequential extent
     for  the  file  is  printed, followed  by  a  summary of the 
     number of extents for the  file  and  the  average number of
     device blocks per extent.

     filestat is a symbolic link to clri .

FILES
     /etc/default/fs
               default local file system type

     /etc/mnttab
               mount table

ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:
     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Availability                | SUNWcsu                     |
    |_____________________________|_____________________________|

SEE ALSO
     fsck(1M), vfstab(4), attributes(5)