showfile(8) — Maintenance
NAME
showfile − displays the attributes of a file
SYNOPSIS
/usr/sbin/showfile [−x] filename ...
FLAG
−xDisplays the full storage allocation map (extent map) for files in an Advanced File System.
DESCRIPTION
The showfile command displays the attributes of one or more Advanced File System (AdvFS) files. The command also displays the extent map of each file. An extent is a contiguous area of disk space that the file system allocates to a file. Simple files have one extent map; striped files have an extent map for every stripe segment.
You can list AdvFS attributes for an individual file or the contents of a directory. Although the showfile command lists both AdvFS and non-AdvFS files, the command displays meaningful information for AdvFS files only.
The showfile command displays the following file attributes:
•Id
The unique number (in hexadecimal format) that identifies the file. Digits to the left of the dot (.) character are equivalent to a UFS inode.
•Vol
The location of primary metadata for the file, expressed as a number. The data extents of the file can reside on another volume.
•PgSz
The page size in 512-byte blocks.
•Pages
The number of pages allocated to the file.
•XtntType
The extent type can be simple, which is a regular AdvFS file without special extents; stripe, which is a striped file; symlink, which is a symbolic link to a file; usf,nfs, and so on. The showfile command cannot display attributes for symbolic links or non-AdvFS files.
•Segs
The number of stripe segments per striped file, which is the number of volumes a striped file crosses. (Applies only to stripe type.)
•SegSz
The number of pages per stripe segment. (Applies only to stripe type.)
•Log
The data logging option is on or off.
•Perf
The efficiency of file-extent allocation, expressed as a percentage of the optimal extent layout. A high percentage, such as 100%, indicates that the AdvFS I/O system has achieved optimal efficiency. A low percentage indicates the need for file defragmentation.
Whereas a simple file has one extent map, a striped file has more than one extent map. An extent map (numbered extentMap:1, extentMap:2, and so on) displays the following information:
•pageOff
The starting page number of the extent.
•pageCnt
The number of pages in the extent.
•vol
The location of the extent, expressed as a number.
•volBlock
The starting block number of the extent.
•blockCnt
The number of blocks in the extent.
•extentCnt
The number of extents.
Note that in order to create striped files or to enable file data logging, you must purchase the POLYCENTER Advanced File System Utilities layered product.
EXAMPLE
The following example displays the AdvFS-specific attributes for all the files in the current working directory:
# showfile ∗
Id Vol PgSz Pages XtntType Segs SegSz Log Perf File
22a.001 1 16 1 simple ∗∗ ∗∗ off 50% Mail
7.001 1 16 1 simple ∗∗ ∗∗ off 20% bin
1d8.001 1 16 1 simple ∗∗ ∗∗ off 33% c
1bff.001 1 16 1 simple ∗∗ ∗∗ off 82% dxMail
218.001 1 16 1 simple ∗∗ ∗∗ off 26% emacs
1ed.001 1 16 0 simple ∗∗ ∗∗ off 100% foo
1ee.001 1 16 1 simple ∗∗ ∗∗ off 77% lib
1c8.001 1 16 1 simple ∗∗ ∗∗ off 94% obj
23f.003 1 16 1 simple ∗∗ ∗∗ off 100% sb
170a.008 1 16 2 simple ∗∗ ∗∗ off 35% t
6.001 1 16 12 simple ∗∗ ∗∗ off 16% tmp
The following example shows the attributes and extent information for the mail file, which is a simple file:
# showfile -x mail
Id Vol PgSz Pages XtntType Segs SegSz Log Perf File
4198.800d 2 16 27 simple ∗∗ ∗∗ off 66% tutorial
extentMap: 1
pageOff pageCnt vol volBlock blockCnt
0 5 2 781552 80
5 12 2 785776 192
17 10 2 786800 160
extentCnt: 3