Current File : //usr/share/man/man8/vfs_preopen.8

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.\"     Title: vfs_preopen
.\"    Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL Stylesheets v1.76.1 <http://docbook.sf.net/>
.\"      Date: 09/18/2013
.\"    Manual: System Administration tools
.\"    Source: Samba 3.6
.\"  Language: English
.\"
.TH "VFS_PREOPEN" "8" "09/18/2013" "Samba 3\&.6" "System Administration tools"
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.SH "NAME"
vfs_preopen \- Hide read latencies for applications reading numbered files
.SH "SYNOPSIS"
.HP \w'\ 'u
vfs objects = preopen
.SH "DESCRIPTION"
.PP
This VFS module is part of the
\fBsamba\fR(7)
suite\&.
.PP
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\&.
.PP
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\*(Aqs request comes along, no disk access is necessary\&.
.PP
This module is stackable\&.
.SH "OPTIONS"
.PP
preopen:names = /pattern/
.RS 4
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
preopen:names=/FRAME*\&.frm/
.RE
.PP
preopen:num_bytes = BYTES
.RS 4
Specifies the number of bytes the helpers should speculatively read, defaults to 1\&.
.RE
.PP
preopen:helpers = NUM\-PROCS
.RS 4
Number of forked helper processes, defaults to 1\&.
.RE
.PP
preopen:queuelen = NUM\-FILES
.RS 4
Number of files that should be speculatively opened\&. Defaults to the 10 subsequent files\&.
.RE
.SH "VERSION"
.PP
This man page is correct for version 3\&.3 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\&.
.PP
The PREOPEN VFS module was created with contributions from Volker Lendecke and the developers at IBM\&.


.\" Oracle has added the ARC stability level to this manual page
.SH ATTRIBUTES
See
.BR attributes (5)
for descriptions of the following attributes:
.sp
.TS
box;
cbp-1 | cbp-1
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE 
=
Availability	service/network/samba
=
Stability	Volatile
.TE 
.PP

.SH NOTES

.\" Oracle has added source availability information to this manual page
This software was built from source available at https://java.net/projects/solaris-userland.  The original community source was downloaded from  http://ftp.samba.org/pub/samba/stable/samba-3.6.25.tar.gz

Further information about this software can be found on the open source community website at http://www.samba.org/.