s3:smbd: avoid invalid lock_order panic triggered by "CTDB_SRVID_RELEASE_IP"
[Samba.git] / docs-xml / manpages / vfs_prealloc.8.xml
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1 <?xml version="1.0" encoding="iso-8859-1"?>
2 <!DOCTYPE refentry PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc">
3 <refentry id="vfs_prealloc.8">
5 <refmeta>
6         <refentrytitle>vfs_prealloc</refentrytitle>
7         <manvolnum>8</manvolnum>
8         <refmiscinfo class="source">Samba</refmiscinfo>
9         <refmiscinfo class="manual">System Administration tools</refmiscinfo>
10         <refmiscinfo class="version">4.0</refmiscinfo>
11 </refmeta>
14 <refnamediv>
15         <refname>vfs_prealloc</refname>
16         <refpurpose>preallocate matching files to a predetermined size</refpurpose>
17 </refnamediv>
19 <refsynopsisdiv>
20         <cmdsynopsis>
21                 <command>vfs objects = prealloc</command>
22         </cmdsynopsis>
23 </refsynopsisdiv>
25 <refsect1>
26         <title>DESCRIPTION</title>
28         <para>This VFS module is part of the
29         <citerefentry><refentrytitle>samba</refentrytitle>
30         <manvolnum>7</manvolnum></citerefentry> suite.</para>
32         <para>The <command>vfs_prealloc</command> VFS module preallocates
33         files to a specified size each time a new file is created. This
34         is useful in environments where files are of a predetermined
35         size will be written to a disk subsystem where extending file
36         allocations is expensive.  </para>
38         <para>This module is stackable.</para>
40 </refsect1>
43 <refsect1>
44         <title>OPTIONS</title>
46         <variablelist>
48                 <varlistentry>
49                 <term>prealloc:EXT = BYTES</term>
50                 <listitem>
51                 <para>Preallocate all files with the extension EXT to
52                 the size specified by BYTES.
53                 </para>
55                 <para>The following suffixes may be applied to BYTES:</para>
56                 <itemizedlist>
57                 <listitem><para><command>K</command> - BYTES is a number of kilobytes</para></listitem>
58                 <listitem><para><command>M</command> - BYTES is a number of megabytes</para></listitem>
59                 <listitem><para><command>G</command> - BYTES is a number of gigabytes</para></listitem>
60                 </itemizedlist>
62                 </listitem>
63                 </varlistentry>
65         </variablelist>
66 </refsect1>
68 <refsect1>
69         <title>EXAMPLES</title>
71         <para>A process writes TIFF files to a Samba share, and the
72         is known these files will almost always be around 4 megabytes
73         (4194304 bytes): </para>
75 <programlisting>
76         <smbconfsection name="[frames]"/>
77         <smbconfoption name="path">/data/frames</smbconfoption>
78         <smbconfoption name="vfs objects">prealloc</smbconfoption>
79         <smbconfoption name="prealloc:tiff">4M</smbconfoption>
80 </programlisting>
81 </refsect1>
83 <refsect1>
84         <title>CAVEATS</title>
85         <para><command>vfs_prealloc</command> is not supported on all
86         platforms and filesystems. Currently only XFS filesystems on
87         Linux and IRIX are supported.
88         </para>
89 </refsect1>
91 <refsect1>
92         <title>VERSION</title>
93         <para>This man page is correct for version 3.0.25 of the Samba suite.
94         </para>
95 </refsect1>
97 <refsect1>
98         <title>AUTHOR</title>
100         <para>The original Samba software and related utilities
101         were created by Andrew Tridgell. Samba is now developed
102         by the Samba Team as an Open Source project similar
103         to the way the Linux kernel is developed.</para>
105 </refsect1>
107 </refentry>