diff options
| author | Jaegeuk Kim <jaegeuk.kim@samsung.com> | 2013-04-29 16:58:39 +0900 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk.kim@samsung.com> | 2013-04-30 12:07:32 +0900 |
| commit | ac5d156c78a68b39955ee9b09498ba93831c77d7 (patch) | |
| tree | 638245b8a39332d3bb2878c5a0a8574e518fcc37 /fs/f2fs/node.c | |
| parent | b743ba78ae4c7c6a6e08e623af824b6208f58019 (diff) | |
| download | linux-ac5d156c78a68b39955ee9b09498ba93831c77d7.tar.bz2 | |
f2fs: modify the number of issued pages to merge IOs
When testing f2fs on an SSD, I found some 128 page IOs followed by 1 page IO
were issued by f2fs_write_node_pages.
This means that there were some mishandling flows which degrades performance.
Previous f2fs_write_node_pages determines the number of pages to be written,
nr_to_write, as follows.
1. The bio_get_nr_vecs returns 129 pages.
2. The bio_alloc makes a room for 128 pages.
3. The initial 128 pages go into one bio.
4. The existing bio is submitted, and a new bio is prepared for the last 1 page.
5. Finally, sync_node_pages submits the last 1 page bio.
The problem is from the use of bio_get_nr_vecs, so this patch replace it
with max_hw_blocks using queue_max_sectors.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Diffstat (limited to 'fs/f2fs/node.c')
| -rw-r--r-- | fs/f2fs/node.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index f14eb7b8b2c4..7209d637f942 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1171,7 +1171,6 @@ static int f2fs_write_node_pages(struct address_space *mapping, struct writeback_control *wbc) { struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb); - struct block_device *bdev = sbi->sb->s_bdev; long nr_to_write = wbc->nr_to_write; /* First check balancing cached NAT entries */ @@ -1185,10 +1184,9 @@ static int f2fs_write_node_pages(struct address_space *mapping, return 0; /* if mounting is failed, skip writing node pages */ - wbc->nr_to_write = bio_get_nr_vecs(bdev); + wbc->nr_to_write = max_hw_blocks(sbi); sync_node_pages(sbi, 0, wbc); - wbc->nr_to_write = nr_to_write - - (bio_get_nr_vecs(bdev) - wbc->nr_to_write); + wbc->nr_to_write = nr_to_write - (max_hw_blocks(sbi) - wbc->nr_to_write); return 0; } |