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.\" Title: vfs_readahead
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.\" Author: [see the "AUTHOR" section]
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.\" Manual: System Administration tools
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.TH "VFS_READAHEAD" "8" "05/10/2010" "Samba 3\&.4" "System Administration tools"
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vfs_readahead \- pre\-load the kernel buffer cache
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\FCvfs objects = readahead\F[]
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This VFS module is part of the
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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\&.
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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\&.
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The offset multiple used is given by the readahead:offset option, which defaults to 0x80000\&.
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The size of the disk read operations performed by
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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\&.
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This module is stackable\&.
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readahead:offset = BYTES
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The offset multiple that causes readahead to be requested of the kernel buffer cache\&.
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readahead:length = BYTES
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The number of bytes requested to be read into the kernel buffer cache on each readahead call\&.
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The following suffixes may be applied to BYTES:
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\- BYTES is a number of kilobytes
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\- BYTES is a number of megabytes
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\- BYTES is a number of gigabytes
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\m[blue]\fBvfs objects = readahead\fR\m[]
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This man page is correct for version 3\&.0\&.25 of the Samba suite\&.
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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\&.