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DSYNC(1)			  mpiFileUtils				DSYNC(1)

NAME
     dsync - synchronize directory trees

SYNOPSIS
     dsync [OPTION] SRC DEST

DESCRIPTION
     Parallel MPI application to synchronize two files or two directory trees.

     dsync  makes DEST match SRC, adding missing entries from DEST, and updating
     existing entries in DEST as necessary so that SRC and DEST  have  identical
     content, ownership, timestamps, and permissions.

     dsync is similar to rsync(1) archive mode for creating and then maintaining
     an identical copy of a source directory tree.

OPTIONS
     --dryrun
	    Show differences without changing anything.

     -b, --batch-files N
	    Batch files into groups of up to size N during copy operation.

     --bufsize SIZE
	    Set  the  I/O buffer to be SIZE bytes.  Units like "MB" and "GB" may
	    immediately follow the number without spaces (e.g. 8MB). The default
	    bufsize is 4MB.

     --chunksize SIZE
	    Multiple processes copy a large file in parallel by dividing it into
	    chunks.  Set chunk to be at minimum SIZE bytes.  Units like "MB" and
	    "GB" can immediately follow the number without spaces  (e.g.  64MB).
	    The default chunksize is 4MB.

     --xattrs WHICH
	    Copy  extended  attributes	("xattrs")  from  source files to target
	    files.  WHICH determines which xattrs are copied.	Options  are  to
	    copy  no xattrs, all xattrs, xattrs not excluded by /etc/xattr.conf,
	    or all xattrs except those which have  special  meaning  to  Lustre.
	    Certain xattrs control Lustre features on a file-by-file basis, such
	    as	how  the file data is distributed across Lustre servers.  Values
	    must be  in  {none,  all,  libattr,  non-lustre}.	The  default  is
	    non-lustre.

     --daos-api API
	    Specify  the  DAOS	API to be used. By default, the API is automati-
	    cally determined based on the container type, where POSIX containers
	    use the DFS API, and all other containers use the DAOS  object  API.
	    Values must be in {DFS, DAOS}.

     -c, --contents
	    Compare  files  byte-by-byte  rather than checking size and mtime to
	    determine whether file contents are different.

     -D, --delete
	    Delete extraneous files from destination.

     -L, --dereference
	    Dereference symbolic links and copy the  target  file  or  directory
	    that each symbolic link refers to.

     -P, --no-dereference
	    Do	not  follow  symbolic  links in source paths. Effectviely allows
	    symbolic links to be copied when the link target  is  not  valid  or
	    there is not permission to read the link's target.

     -s, --direct
	    Use O_DIRECT to avoid caching file data.

     --open-noatime
	    Open files with O_NOATIME flag.

     --link-dest DIR
	    Create  hardlink  in  DEST	to  files  in DIR when file is unchanged
	    rather than create a new file. One can use this option  to	conserve
	    storage space during an incremental backup.

	    For  example  in  the  following, any file that would be copied from
	    /src to /src.bak.inc that is the same as the file  already	existing
	    in /src.bak will instead be hardlinked to the file in /src.bak:

	    # initial backup of /src dsync /src /src.bak

	    #  incremental  backup  of	/src  dsync  --link-dest  /src.bak  /src
	    /src.bak.inc

     -S, --sparse
	    Create sparse files when possible.

     --progress N
	    Print progress message to stdout approximately every N seconds.  The
	    number of seconds must be a non-negative integer.  A value of 0 dis-
	    ables progress messages.

     -v, --verbose
	    Run in verbose mode. Prints a list of statistics/timing data for the
	    command. Files walked, started,  completed,  seconds,  files,  bytes
	    read, byte rate, and file rate.

     -q, --quiet
	    Run tool silently. No output is printed.

     -h, --help
	    Print the command usage, and the list of options available.

EXAMPLES
     1. Synchronize dir2 to match dir1:

     mpirun -np 128 dsync /path/to/dir1 /path/to/dir2

SEE ALSO
     The  mpiFileUtils	source code and all documentation may be downloaded from
     <https://github.com/hpc/mpifileutils>

AUTHOR
     HPC

COPYRIGHT
     2022, LLNL/LANL/UT-Battelle/DDN

0.12				  Jan 29, 2025				DSYNC(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=dsync&sektion=1&manpath=FreeBSD+Ports+15.1.quarterly>

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