original_kernel/fs/fat
OGAWA Hirofumi 9f966be899 fat: optimize fat_count_free_clusters()
On large partition, scanning the free clusters is very slow if users
doesn't use "usefree" option.

For optimizing it, this patch uses sb_breadahead() to read of FAT
sectors. On some user's 15GB partition, this patch improved it very
much (1min => 600ms).

The following is the result of 2GB partition on my machine.

without patch:
	root@devron (/)# time df -h > /dev/null

	real    0m1.202s
	user    0m0.000s
	sys     0m0.440s

with patch:
	root@devron (/)# time df -h > /dev/null

	real    0m0.378s
	user    0m0.012s
	sys     0m0.168s

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-08 16:10:35 -08:00
..
Makefile
cache.c Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
dir.c
fatent.c fat: optimize fat_count_free_clusters() 2008-01-08 16:10:35 -08:00
file.c
inode.c exportfs: make struct export_operations const 2007-10-22 08:13:21 -07:00
misc.c