f2fs: support subsectional garbage collection

Section is minimal garbage collection unit of f2fs, in zoned block
device, or ancient block mapping flash device, in order to improve
GC efficiency, we can align GC unit to lower device erase unit,
normally, it consists of multiple of segments.

Once background or foreground GC triggers, it brings a large number
of IOs, which will impact user IO, and also occupy cpu/memory resource
intensively.

So, to reduce impact of GC on large size section, this patch supports
subsectional GC, in one cycle of GC, it only migrate partial segment{s}
in victim section. Currently, by default, we use sbi->segs_per_sec as
migration granularity.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Chao Yu
2018-10-24 18:37:27 +08:00
committed by Jaegeuk Kim
parent 2c70c5e387
commit e3080b0120
3 changed files with 39 additions and 6 deletions

View File

@@ -2692,7 +2692,10 @@ static void init_sb_info(struct f2fs_sb_info *sbi)
sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
sbi->cur_victim_sec = NULL_SECNO;
sbi->next_victim_seg[BG_GC] = NULL_SEGNO;
sbi->next_victim_seg[FG_GC] = NULL_SEGNO;
sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
sbi->migration_granularity = sbi->segs_per_sec;
sbi->dir_level = DEF_DIR_LEVEL;
sbi->interval_time[CP_TIME] = DEF_CP_INTERVAL;