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.TH vzfsync 8 "31 Mar 2014" "OpenVZ" "Containers"
.SH NAME
vzfsync \- perform fsync/fdatasync/fadvise on files
.SH SYNOPSIS
.SY vzfsync
{
.BR -s , --sync
|
.BR -d , --datasync
}
.OP -n\fR,\fB--dontneed
.B file
.OP file ...
.YS
.SY vzfsync
.B --help
.YS
.SH DESCRIPTION
This utility performs
.BR fsync (2)
or
.BR fdatasync(2)
for every supplied file name.
It can also optionally perform
.BR posix_fadvise (2)
with the argument of
.BR POSIX_FADV_DONTNEED .
.P
It is used from within
.BR vzmigrate (8)
utility for live migration, right after copying ploop delta files
(and before suspending a container) to sync those copied files to disk
in order to optimize subsequent ploop mount time and, utlimately,
container frozen time.
.SH OPTIONS
.TP
.BR -s , --sync
Perform fsync.
.TP
.BR -d , --datasync
Perform fdatasync.
.TP
.BR -n , --dontneed
Perform posix_fadvise(POSIX_FADV_DONTNEED).
.SH EXIT STATUS
Returns 0 upon success, or an appropriate error code in case of an error:
.IP 1
Invalid usage
.IP 2
Failed to perform some requested operations on one or many files.
.SH SEE ALSO
.BR fsync (2),
.BR fdatasync (2),
.BR posix_fadvise (2).
.SH LICENSE
Copyright (C) 2014, Parallels, Inc. Licensed under GNU GPL v2.