linux/fs/f2fs
Chao Yu 19b2c30d3c f2fs: update extent tree in batches
This patch introduce a new helper f2fs_update_extent_tree_range which can
do extent mapping update at a specified range.

The main idea is:
1) punch all mapping info in extent node(s) which are at a specified range;
2) try to merge new extent mapping with adjacent node, or failing that,
   insert the mapping into extent tree as a new node.

In order to see the benefit, I add a function for stating time stamping
count as below:

uint64_t rdtsc(void)
{
	uint32_t lo, hi;
	__asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
	return (uint64_t)hi << 32 | lo;
}

My test environment is: ubuntu, intel i7-3770, 16G memory, 256g micron ssd.

truncation path:	update extent cache from truncate_data_blocks_range
non-truncataion path:	update extent cache from other paths
total:			all update paths

a) Removing 128MB file which has one extent node mapping whole range of
file:
1. dd if=/dev/zero of=/mnt/f2fs/128M bs=1M count=128
2. sync
3. rm /mnt/f2fs/128M

Before:
		total		count		average
truncation:	7651022		32768		233.49

Patched:
		total		count		average
truncation:	3321		33		100.64

b) fsstress:
fsstress -d /mnt/f2fs -l 5 -n 100 -p 20
Test times:		5 times.

Before:
		total		count		average
truncation:	5812480.6	20911.6		277.95
non-truncation:	7783845.6	13440.8		579.12
total:		13596326.2	34352.4		395.79

Patched:
		total		count		average
truncation:	1281283.0	3041.6		421.25
non-truncation:	7355844.4	13662.8		538.38
total:		8637127.4	16704.4		517.06

1) For the updates in truncation path:
 - we can see updating in batches leads total tsc and update count reducing
   explicitly;
 - besides, for a single batched updating, punching multiple extent nodes
   in a loop, result in executing more operations, so our average tsc
   increase intensively.
2) For the updates in non-truncation path:
 - there is a little improvement, that is because for the scenario that we
   just need to update in the head or tail of extent node, new interface
   optimize to update info in extent node directly, rather than removing
   original extent node for updating and then inserting that updated one
   into cache as new node.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-26 11:50:35 -07:00
..
acl.c f2fs: make posix_acl_create() safer and cleaner 2015-05-07 11:38:31 -07:00
acl.h f2fs: avoid deadlock on init_inode_metadata 2014-11-03 16:07:33 -08:00
checkpoint.c f2fs: use __GFP_NOFAIL to avoid infinite loop 2015-08-24 09:37:21 -07:00
crypto_fname.c f2fs crypto: clean up error handling in f2fs_fname_setup_filename 2015-06-01 16:21:08 -07:00
crypto_key.c f2fs crypto: delete an unnecessary check before the function call "key_put" 2015-08-04 14:09:52 -07:00
crypto_policy.c f2fs crypto: do not set encryption policy for non-directory by ioctl 2015-06-01 16:21:07 -07:00
crypto.c f2fs crypto: add alloc_bounce_page 2015-06-11 15:04:20 -07:00
data.c f2fs: fix incorrect mapping for bmap 2015-08-21 22:45:14 -07:00
debug.c f2fs: adjust showing of extent cache stat 2015-08-21 22:45:16 -07:00
dir.c f2fs: avoid clear valid page 2015-08-20 09:00:06 -07:00
extent_cache.c f2fs: update extent tree in batches 2015-08-26 11:50:35 -07:00
f2fs_crypto.h f2fs crypto: remove alloc_page for bounce_page 2015-06-01 16:21:10 -07:00
f2fs.h f2fs: update extent tree in batches 2015-08-26 11:50:35 -07:00
file.c f2fs: update extent tree in batches 2015-08-26 11:50:35 -07:00
gc.c f2fs: retry gc if one section is not successfully reclaimed 2015-08-20 09:00:12 -07:00
gc.h f2fs: add new ioctl F2FS_IOC_GARBAGE_COLLECT 2015-08-04 14:09:58 -07:00
hash.c f2fs: introduce dot and dotdot name check 2015-05-28 15:41:34 -07:00
inline.c f2fs: avoid unneeded initializing when converting inline dentry 2015-08-24 09:38:20 -07:00
inode.c f2fs: fix to release inode correctly 2015-08-24 16:35:59 -07:00
Kconfig f2fs: fix typo 2015-08-21 22:43:32 -07:00
Makefile f2fs: maintain extent cache in separated file 2015-08-04 14:09:58 -07:00
namei.c f2fs: go out for insert_inode_locked failure 2015-08-20 09:00:13 -07:00
node.c f2fs: fix to release inode correctly 2015-08-24 16:35:59 -07:00
node.h f2fs: move existing definitions into f2fs.h 2015-05-28 15:41:27 -07:00
recovery.c f2fs: do not write any node pages related to orphan inodes 2015-08-20 08:59:42 -07:00
segment.c f2fs: use __GFP_NOFAIL to avoid infinite loop 2015-08-24 09:37:21 -07:00
segment.h f2fs: avoid a build warning 2015-08-14 16:02:15 -07:00
shrinker.c f2fs: shrink free_nids entries 2015-08-20 09:00:06 -07:00
super.c f2fs: do not write any node pages related to orphan inodes 2015-08-20 08:59:42 -07:00
trace.c f2fs: add sbi and page pointer in f2fs_io_info 2015-05-28 15:41:32 -07:00
trace.h f2fs: add sbi and page pointer in f2fs_io_info 2015-05-28 15:41:32 -07:00
xattr.c f2fs: correct return value of ->setxattr 2015-08-04 14:09:59 -07:00
xattr.h f2fs crypto: add encryption xattr support 2015-05-28 15:41:47 -07:00