.\"     Title: vfs_prealloc
.\"    Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL Stylesheets v1.74.0 <http://docbook.sf.net/>
.\"      Date: 06/18/2010
.\"    Manual: System Administration tools
.\"    Source: Samba 3.5
.\"  Language: English
.\"
.TH "VFS_PREALLOC" "8" "06/18/2010" "Samba 3\&.5" "System Administration tools"
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.\" * MAIN CONTENT STARTS HERE *
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.SH "Name"
vfs_prealloc \- preallocate matching files to a predetermined size
.SH "Synopsis"
.fam C
.HP \w'\ 'u
\FCvfs objects = prealloc\F[]
.fam
.SH "DESCRIPTION"
.PP
This VFS module is part of the
\fBsamba\fR(7)
suite\&.
.PP
The
\FCvfs_prealloc\F[]
VFS module preallocates files to a specified size each time a new file is created\&. This is useful in environments where files are of a predetermined size will be written to a disk subsystem where extending file allocations is expensive\&.
.PP
This module is stackable\&.
.SH "OPTIONS"
.PP
prealloc:EXT = BYTES
.RS 4
Preallocate all files with the extension EXT to the size specified by BYTES\&.
.sp
The following suffixes may be applied to BYTES:
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
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\FCK\F[]
\- BYTES is a number of kilobytes
.RE
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\- BYTES is a number of megabytes
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\- BYTES is a number of gigabytes
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.RE
.RE
.SH "EXAMPLES"
.PP
A process writes TIFF files to a Samba share, and the is known these files will almost always be around 4 megabytes (4194304 bytes):
.sp
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        \fI[frames]\fR
	\m[blue]\fBpath = /data/frames\fR\m[]
	\m[blue]\fBvfs objects = prealloc\fR\m[]
	\m[blue]\fBprealloc:tiff = 4M\fR\m[]
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.SH "CAVEATS"
.PP
\FCvfs_prealloc\F[]
is not supported on all platforms and filesystems\&. Currently only XFS filesystems on Linux and IRIX are supported\&.
.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\&.