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VFS_READAHEAD(8)	  System Administration	tools	      VFS_READAHEAD(8)

NAME
       vfs_readahead - pre-load	the kernel buffer cache

SYNOPSIS
       vfs objects = readahead

DESCRIPTION
       This VFS	module is part of the samba(7) suite.

       This vfs_readahead VFS module detects read requests at multiples	of a
       given offset (hex 0x80000 by default) and then tells the	kernel via
       either the readahead system call	(on Linux) or the posix_fadvise	system
       call to pre-fetch this data into	the buffer cache.

       This module is useful for Windows Vista clients reading data using the
       Windows Explorer	program, which asynchronously does multiple file read
       requests	at offset boundaries of	0x80000	bytes.

       The offset multiple used	is given by the	readahead:offset option, which
       defaults	to 0x80000.

       The size	of the disk read operations performed by vfs_readahead is
       determined by the readahead:length option. By default this is set to
       the same	value as the readahead:offset option and if not	set explicitly
       will use	the current value of readahead:offset.

       This module is stackable.

OPTIONS
       readahead:offset	= BYTES
	   The offset multiple that causes readahead to	be requested of	the
	   kernel buffer cache.

       readahead:length	= BYTES
	   The number of bytes requested to be read into the kernel buffer
	   cache on each readahead call.

       The following suffixes may be applied to	BYTES:

	      o	  K - BYTES is a number	of kilobytes

	      o	  M - BYTES is a number	of megabytes

	      o	  G - BYTES is a number	of gigabytes

EXAMPLES
		[hypothetical]
		vfs objects = readahead

VERSION
       This man	page is	part of	version	4.11.11	of the Samba suite.

AUTHOR
       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.

Samba 4.11.11			  07/01/2020		      VFS_READAHEAD(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | VERSION | AUTHOR

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