mirror of
https://github.com/samba-team/samba.git
synced 2024-12-24 21:34:56 +03:00
fcaeffde4e
BUG: https://bugzilla.samba.org/show_bug.cgi?id=9531 Signed-off-by: Karolin Seeger <kseeger@samba.org> Reviewed-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andreas Schneider <asn@samba.org> Autobuild-User(master): Andreas Schneider <asn@cryptomilk.org> Autobuild-Date(master): Wed Dec 13 17:22:01 CET 2017 on sn-devel-144
116 lines
3.1 KiB
XML
116 lines
3.1 KiB
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_preopen.8">
|
|
|
|
<refmeta>
|
|
<refentrytitle>vfs_preopen</refentrytitle>
|
|
<manvolnum>8</manvolnum>
|
|
<refmiscinfo class="source">Samba</refmiscinfo>
|
|
<refmiscinfo class="manual">System Administration tools</refmiscinfo>
|
|
<refmiscinfo class="version">&doc.version;</refmiscinfo>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>vfs_preopen</refname>
|
|
<refpurpose>Hide read latencies for applications reading numbered files</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsynopsisdiv>
|
|
<cmdsynopsis>
|
|
<command>vfs objects = preopen</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>This module assists applications that want to read numbered
|
|
files in sequence with very strict latency requirements. One area
|
|
where this happens in video streaming applications that want to read
|
|
one file per frame.</para>
|
|
|
|
<para>When you use this module, a number of helper processes is
|
|
started that speculatively open files and read a number of bytes to
|
|
prime the file system cache, so that later on when the real
|
|
application's request comes along, no disk access is necessary.</para>
|
|
|
|
<para>This module is stackable.</para>
|
|
|
|
</refsect1>
|
|
|
|
|
|
<refsect1>
|
|
<title>OPTIONS</title>
|
|
|
|
<variablelist>
|
|
|
|
<varlistentry>
|
|
<term>preopen:names = /pattern/</term>
|
|
<listitem>
|
|
<para>
|
|
preopen:names specifies the file name pattern which should
|
|
trigger the preopen helpers to do their work. We assume that
|
|
the files are numbered incrementally. So if your file names
|
|
are numbered FRAME00000.frm FRAME00001.frm and so on you would
|
|
list them as <command>preopen:names=/FRAME*.frm/</command>
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>preopen:num_bytes = BYTES</term>
|
|
<listitem>
|
|
<para>
|
|
Specifies the number of bytes the helpers should speculatively
|
|
read, defaults to 1.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>preopen:helpers = NUM-PROCS</term>
|
|
<listitem>
|
|
<para>
|
|
Number of forked helper processes, defaults to 1.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>preopen:queuelen = NUM-FILES</term>
|
|
<listitem>
|
|
<para>
|
|
Number of files that should be speculatively opened. Defaults
|
|
to the 10 subsequent files.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
</variablelist>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>VERSION</title>
|
|
<para>This man page is correct for version &doc.version; 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>
|
|
|
|
<para>The PREOPEN VFS module was created with contributions from
|
|
Volker Lendecke and the developers at IBM.
|
|
</para>
|
|
</refsect1>
|
|
|
|
</refentry>
|