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+.\" -*- nroff -*-
+.TH E2FREEFRAG 8 "@E2FSPROGS_MONTH@ @E2FSPROGS_YEAR@" "E2fsprogs version @E2FSPROGS_VERSION@"
+.SH NAME
+e2freefrag \- report free space fragmentation information
+.SH SYNOPSIS
+.B e2freefrag
+[
+.B \-c chunk_kb
+]
+[
+.B \-h
+]
+.B filesys
+
+.SH DESCRIPTION
+.B e2freefrag
+is used to report free space fragmentation on ext2/3/4 file systems.
+.I filesys
+is the file system device name (e.g.
+.IR /dev/hdc1 ", " /dev/md0 ).
+The
+.B e2freefrag
+program will scan the block bitmap information to check how many free blocks
+are present as contiguous and aligned free space. The percentage of contiguous
+free blocks of size and of alignment
+.I chunk_kb
+is reported. It also displays the minimum/maximum/average free chunk size in
+the file system, along with a histogram of all free chunks. This information
+can be used to gauge the level of free space fragmentation in the file system.
+.SH OPTIONS
+.TP
+.BI \-c " chunk_kb"
+If a chunk size is specified, then
+.B e2freefrag
+will print how many free chunks of size
+.I chunk_kb
+are available in units of kilobytes (Kb). The chunk size must be a
+power of two and be larger than file system block size.
+.TP
+.B \-h
+Print the usage of the program.
+.SH EXAMPLE
+# e2freefrag /dev/vgroot/lvhome
+.br
+Device: /dev/vgroot/lvhome
+.br
+Blocksize: 4096 bytes
+.br
+Total blocks: 1504085
+.br
+Free blocks: 292995 (19.5%)
+.br
+
+Min. free extent: 4 KB
+.br
+Max. free extent: 24008 KB
+.br
+Avg. free extent: 252 KB
+.br
+
+HISTOGRAM OF FREE EXTENT SIZES:
+.br
+Extent Size Range : Free extents Free Blocks Percent
+.br
+ 4K... 8K- : 704 704 0.2%
+.br
+ 8K... 16K- : 810 1979 0.7%
+.br
+ 16K... 32K- : 843 4467 1.5%
+.br
+ 32K... 64K- : 579 6263 2.1%
+.br
+ 64K... 128K- : 493 11067 3.8%
+.br
+ 128K... 256K- : 394 18097 6.2%
+.br
+ 256K... 512K- : 281 25477 8.7%
+.br
+ 512K... 1024K- : 253 44914 15.3%
+.br
+ 1M... 2M- : 143 51897 17.7%
+.br
+ 2M... 4M- : 73 50683 17.3%
+.br
+ 4M... 8M- : 37 52417 17.9%
+.br
+ 8M... 16M- : 7 19028 6.5%
+.br
+ 16M... 32M- : 1 6002 2.0%
+.SH AUTHOR
+This version of e2freefrag was written by Rupesh Thakare, and modified by
+Andreas Dilger <adilger@sun.com>, and Kalpak Shah.
+.SH SEE ALSO
+.IR debugfs (8),
+.IR dumpe2fs (8),
+.IR e2fsck (8)