path: root/docs/manpages/vfs_commit.8

.\"     Title: vfs_commit
.\"    Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL Stylesheets v1.74.0 <http://docbook.sf.net/>
.\"      Date: 06/16/2009
.\"    Manual: System Administration tools
.\"    Source: Samba 3.3
.\"  Language: English
.\"
.TH "VFS_COMMIT" "8" "06/16/2009" "Samba 3\&.3" "System Administration tools"
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.\" * MAIN CONTENT STARTS HERE *
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.SH "Name"
vfs_commit \- flush dirty data at specified intervals
.SH "Synopsis"
.fam C
.HP \w'\ 'u
\FCvfs objects = commit\F[]
.fam
.SH "DESCRIPTION"
.PP
This VFS module is part of the
\fBsamba\fR(7)
suite\&.
.PP
The
\FCvfs_commit\F[]
VFS module keeps track of the amount of data written to a file and synchronizes it to disk when a specified amount accumulates\&.
.PP
\FCvfs_commit\F[]
is useful in two circumstances\&. First, if you have very precious data, the impact of unexpected power loss can be minimized by a small commit:dthresh value\&. Secondly, write performance can be improved on some systems by flushing file data early and at regular intervals\&.
.PP
This module is stackable\&.
.SH "OPTIONS"
.PP
commit:dthresh = BYTES
.RS 4
Synchronize file data each time the specified number of bytes has been written\&.
.sp
The following suffixes may be applied to BYTES:
.sp
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.ie n \{\
\h'-04'\(bu\h'+03'\c
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\- BYTES is a number of kilobytes
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\- BYTES is a number of megabytes
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.RE
.SH "EXAMPLES"
.PP
Synchronize the file data on the [precious] share after every 512 kilobytes (524288 bytes) of data is written:
.sp
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        \fI[precious]\fR
	\m[blue]\fBpath = /data/precious\fR\m[]
	\m[blue]\fBvfs objects = commit\fR\m[]
	\m[blue]\fBcommit:dthresh = 512K\fR\m[]
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.SH "CAVEATS"
.PP
On some systems, the data synchronization performed by
\FCcommit\F[]
may reduce performance\&.
.SH "VERSION"
.PP
This man page is correct for version 3\&.0\&.25 of the Samba suite\&.
.SH "AUTHOR"
.PP
The original Samba software and related utilities were created by Andrew Tridgell\&. Samba is now developed by the Samba Team as an Open Source project similar to the way the Linux kernel is developed\&.