PAGE_CACHE_SYNC_READ(9) Memory Management in Linux PAGE_CACHE_SYNC_READ(9)NAME
page_cache_sync_readahead - generic file readahead
void page_cache_sync_readahead(struct address_space * mapping, struct file_ra_state * ra, struct file * filp, pgoff_t offset,
unsigned long req_size);
address_space which holds the pagecache and I/O vectors
file_ra_state which holds the readahead state
passed on to ->readpage and ->readpages
start offset into mapping, in pagecache page-sized units
hint: total size of the read which the caller is performing in pagecache pages
page_cache_sync_readahead should be called when a cache miss happened: it will submit the read. The readahead logic may decide to piggyback
more pages onto the read request if access patterns suggest it will improve performance.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 PAGE_CACHE_SYNC_READ(9)
Check Out this Related Man Page
VFS_READAHEAD(8) System Administration tools VFS_READAHEAD(8)NAME
vfs_readahead - pre-load the kernel buffer cache
vfs objects = readahead
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.
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
vfs objects = readahead
This man page is correct for version 3.0.25 of the Samba suite.
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 4.0 06/17/2014 VFS_READAHEAD(8)
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