Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
TRIM(8)			FreeBSD	System Manager's Manual		       TRIM(8)

     trim -- erase device blocks that have no needed contents

     trim [-Nfqv] [-[lo] offset[K|k|M|m|G|g|T|t]] [-r rfile] device ...

     The trim utility erases specified region of the device.  It is mostly
     relevant for storage that implement trim (like flash based, or thinly
     provisioned storage).  All	erased data is lost.

     The following options are available:

     -N	     Do	not actually erase anything but	show what it would do (dry
	     run).  Implies -v.	 This is the default.  Overrides -f.

     -f	     Perform the operation.  Overrides -N.

     -l	offset[K|k|M|m|G|g|T|t]

     -o	offset[K|k|M|m|G|g|T|t]
	     Specify the length	-l of the region to trim or its	offset -o from
	     the beginning of the device.  The whole device is erased by
	     default unless one	or both	of these options are presented.

	     The argument may be suffixed with one of K, M, G or T (either up-
	     per or lower case)	to indicate a multiple of Kilobytes,
	     Megabytes,	Gigabytes or Terabytes respectively.

     -q	     Do	not output anything except of possible error messages (quiet
	     mode).  Overrides -v.

     -r	rfile
	     Uses the length of	given rfile as length of the region to erase.
	     The whole device is erased	by default.

     -v	     Show offset and length of actual region being erased, in bytes.

     Later options override previous ones.

     Note that actual success of the operation depends of underlying device
     driver such as ada(4), da(4) and others.  Refer to	corresponding manual
     pages for detail on possible caveats in low level support for ATA TRIM or
     SCSI UNMAP	commands.

     The trim utility exits 0 on success, and >0 if an error occurs.  If the
     final erase operation fails for an	argument, the trim utility returns
     exit code 1.  It can also return one of the exit codes defined in
     sysexits(3), as follows:

     EX_USAGE	     The specified offset or length of the region is incor-

     EX_OSERR	     There is no enough	memory to proceed.

     EX_NOINPUT	     The specified rfile cannot	be opened (perhaps, it does
		     not exist).

     EX_IOERR	     The specified rfile cannot	be examined for	its size due
		     to	some system input/output error.

     EX_DATAERR	     The specified rfile is not	regular	file, directory	nor
		     special device, so	its size cannot	be examined.

     EX_UNAVAILABLE  The specified rfile is special device file	not supporting
		     DIOCGMEDIASIZE ioctl(2) (probably not a disk), so its
		     size cannot be examined.

     ioctl(2), sysexits(3), ada(4), da(4), nda(4)

     The trim utility first appeared in	FreeBSD	12.1.

     The trim utility was written by Eugene Grosbein <>.

FreeBSD	13.0		       January 18, 2019			  FreeBSD 13.0


Want to link to this manual page? Use this URL:

home | help