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VFS_READAHEAD(8)                                                                            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_fad-vise posix_fadvise
       vise 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:

         K - BYTES is a number of kilobytes

         M - BYTES is a number of megabytes

         G - BYTES is a number of gigabytes

EXAMPLES
            [hypothetical]
            vfs objects = readahead


VERSION
       This man page is correct for version 3.0.25 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 devel-oped. developed.
       oped.




                                                                                            VFS_READAHEAD(8)