source: vendor/3.6.25/docs-xml/manpages-3/vfs_commit.8.xml

<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE refentry PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc">
<refentry id="vfs_commit.8">

<refmeta>
        <refentrytitle>vfs_commit</refentrytitle>
        <manvolnum>8</manvolnum>
        <refmiscinfo class="source">Samba</refmiscinfo>
        <refmiscinfo class="manual">System Administration tools</refmiscinfo>
        <refmiscinfo class="version">3.6</refmiscinfo>
</refmeta>


<refnamediv>
        <refname>vfs_commit</refname>
        <refpurpose>flush dirty data at specified intervals</refpurpose>
</refnamediv>

<refsynopsisdiv>
        <cmdsynopsis>
                <command>vfs objects = commit</command>
        </cmdsynopsis>
</refsynopsisdiv>

<refsect1>
        <title>DESCRIPTION</title>

        <para>This VFS module is part of the
        <citerefentry><refentrytitle>samba</refentrytitle>
        <manvolnum>7</manvolnum></citerefentry> suite.</para>

        <para>The <command>vfs_commit</command> VFS module keeps track of
        the amount of data written to a file and synchronizes it to
        disk when a specified amount accumulates.
        </para>

        <para><command>vfs_commit</command> 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.</para>

        <para>This module is stackable.</para>

</refsect1>


<refsect1>
        <title>OPTIONS</title>

        <variablelist>

                <varlistentry>
                <term>commit:dthresh = BYTES</term>
                <listitem>
                <para>Synchronize file data each time the specified
                number of bytes has been written.
                </para>

                <para>The following suffixes may be applied to BYTES:</para>
                <itemizedlist>
                <listitem><para><command>K</command> - BYTES is a number of kilobytes</para></listitem>
                <listitem><para><command>M</command> - BYTES is a number of megabytes</para></listitem>
                <listitem><para><command>G</command> - BYTES is a number of gigabytes</para></listitem>
                </itemizedlist>

                </listitem>
                </varlistentry>

        </variablelist>
</refsect1>

<refsect1>
        <title>EXAMPLES</title>

        <para>Synchronize the file data on the [precious] share after
        every 512 kilobytes (524288 bytes) of data is written:</para>
<programlisting>
        <smbconfsection name="[precious]"/>
        <smbconfoption name="path">/data/precious</smbconfoption>
        <smbconfoption name="vfs objects">commit</smbconfoption>
        <smbconfoption name="commit:dthresh">512K</smbconfoption>
</programlisting>
</refsect1>

<refsect1>
        <title>CAVEATS</title>
        <para>On some systems, the data synchronization performed by
        <command>commit</command> may reduce performance.
        </para>
</refsect1>

<refsect1>
        <title>VERSION</title>
        <para>This man page is correct for version 3.0.25 of the Samba suite.
        </para>
</refsect1>

<refsect1>
        <title>AUTHOR</title>

        <para>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.</para>

</refsect1>

</refentry>