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E2FREEFRAG(8)		    System Manager's Manual		 E2FREEFRAG(8)

NAME
       e2freefrag - report free	space fragmentation information

SYNOPSIS
       e2freefrag [ -c chunk_kb	] [ -h ] filesys

DESCRIPTION
       e2freefrag  is used to report free space	fragmentation on ext2/3/4 file
       systems.	 filesys is  the  filesystem  device  name  (e.g.   /dev/hdc1,
       /dev/md0).   The	e2freefrag program will	scan the block bitmap informa-
       tion 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	chunk_kb is reported.	It  also  displays  the	 mini-
       mum/maximum/average  free  chunk	 size  in the filesystem, along	with a
       histogram of all	free chunks.  This information can be  used  to	 gauge
       the level of free space fragmentation in	the filesystem.

OPTIONS
       -c chunk_kb
	      If  a  chunk  size  is specified,	then e2freefrag	will print how
	      many free	chunks of size chunk_kb	 are  available	 in  units  of
	      kilobytes	 (Kb).	 The  chunk size must be a power of two	and be
	      larger than filesystem block size.

       -h     Print the	usage of the program.

EXAMPLE
       # e2freefrag /dev/vgroot/lvhome
       Device: /dev/vgroot/lvhome
       Blocksize: 4096 bytes
       Total blocks: 1504085
       Free blocks: 292995 (19.5%)

       Min. free extent: 4 KB
       Max. free extent: 24008 KB
       Avg. free extent: 252 KB

       HISTOGRAM OF FREE EXTENT	SIZES:
       Extent Size Range :   Free extents   Free Blocks	 Percent
	   4K...    8K-	:	    704		  704	  0.2%
	   8K...   16K-	:	    810		 1979	  0.7%
	  16K...   32K-	:	    843		 4467	  1.5%
	  32K...   64K-	:	    579		 6263	  2.1%
	  64K...  128K-	:	    493		11067	  3.8%
	 128K...  256K-	:	    394		18097	  6.2%
	 256K...  512K-	:	    281		25477	  8.7%
	 512K... 1024K-	:	    253		44914	 15.3%
	   1M...    2M-	:	    143		51897	 17.7%
	   2M...    4M-	:	     73		50683	 17.3%
	   4M...    8M-	:	     37		52417	 17.9%
	   8M...   16M-	:	      7		19028	  6.5%
	  16M...   32M-	:	      1		 6002	  2.0%

AUTHOR
       This version of e2freefrag was written by Rupesh	Thakare, and  modified
       by Andreas Dilger <adilger@sun.com>, and	Kalpak Shah.

SEE ALSO
       debugfs(8), dumpe2fs(8),	e2fsck(8)

E2fsprogs version 1.45.6	  March	2020			 E2FREEFRAG(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLE | AUTHOR | SEE ALSO

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