mirror of https://gitee.com/openkylin/samba.git
69 lines
2.8 KiB
Groff
69 lines
2.8 KiB
Groff
'\" t
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.\" Title: vfs_aio_fork
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.\" Author: [see the "AUTHOR" section]
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.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
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.\" Date: 01/28/2020
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.\" Manual: System Administration tools
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.\" Source: Samba 4.11.6
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.\" Language: English
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.\"
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.TH "VFS_AIO_FORK" "8" "01/28/2020" "Samba 4\&.11\&.6" "System Administration tools"
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.\" * MAIN CONTENT STARTS HERE *
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.\" -----------------------------------------------------------------
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.SH "NAME"
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vfs_aio_fork \- implement async I/O in Samba vfs
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.SH "SYNOPSIS"
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.HP \w'\ 'u
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vfs objects = aio_fork
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.SH "DESCRIPTION"
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.PP
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This VFS module is part of the
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\fBsamba\fR(7)
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suite\&.
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.PP
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The
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aio_fork
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VFS module enables async I/O for Samba on platforms where the system level Posix AIO interface is insufficient\&. Posix AIO can suffer from severe limitations\&. For example, on some Linux versions the real\-time signals that it uses are broken under heavy load\&. Other systems only allow AIO when special kernel modules are loaded or only allow a certain system\-wide amount of async requests being scheduled\&. Systems based on glibc (most Linux systems) only allow a single outstanding request per file descriptor\&.
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.PP
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To work around all these limitations, the aio_fork module was written\&. It uses forked helper processes instead of the internal Posix AIO interface to create asynchronousity for read and write calls\&. It has no parameters, it will create helper processes when async requests come in as needed\&. Idle helper processes will be removed every 30 seconds\&.
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.PP
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This module is stackable\&.
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.SH "EXAMPLES"
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.PP
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Straight forward use:
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.sp
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.if n \{\
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.RS 4
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.\}
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.nf
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\fI[cooldata]\fR
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\m[blue]\fBpath = /data/ice\fR\m[]
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\m[blue]\fBvfs objects = aio_fork\fR\m[]
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.fi
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.if n \{\
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.RE
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.\}
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.SH "VERSION"
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.PP
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This man page is part of version 4\&.11\&.6 of the Samba suite\&.
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.SH "AUTHOR"
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.PP
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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\&.
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