If f2fs is running on top of very small devices, it's worth to avoid abusing free LBAs. In order to achieve that, this patch introduces some parameter tuning.
Signed-off-by: Jaegeuk Kim <[email protected]> --- fs/f2fs/segment.h | 2 ++ fs/f2fs/super.c | 14 ++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index f11c4bc82c78..dbb774aaf387 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -596,6 +596,8 @@ static inline int utilization(struct f2fs_sb_info *sbi) #define DEF_MIN_FSYNC_BLOCKS 8 #define DEF_MIN_HOT_BLOCKS 16 +#define SMALL_VOLUME_SEGMENTS (16 * 512) /* 16GB */ + enum { F2FS_IPU_FORCE, F2FS_IPU_SSR, diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index b7c0bdd1e532..9515c10eebad 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -2512,6 +2512,18 @@ static int f2fs_scan_devices(struct f2fs_sb_info *sbi) return 0; } +static void f2fs_tuning_parameters(struct f2fs_sb_info *sbi) +{ + struct f2fs_sm_info *sm_i = SM_I(sbi); + + /* adjust parameters according to the volume size */ + if (sm_i->main_segments <= SMALL_VOLUME_SEGMENTS) { + sbi->alloc_mode = ALLOC_MODE_REUSE; + sm_i->dcc_info->discard_granularity = 1; + sm_i->ipu_policy = 1 << F2FS_IPU_FORCE; + } +} + static int f2fs_fill_super(struct super_block *sb, void *data, int silent) { struct f2fs_sb_info *sbi; @@ -2864,6 +2876,8 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) f2fs_join_shrinker(sbi); + f2fs_tuning_parameters(sbi); + f2fs_msg(sbi->sb, KERN_NOTICE, "Mounted with checkpoint version = %llx", cur_cp_version(F2FS_CKPT(sbi))); f2fs_update_time(sbi, CP_TIME); -- 2.15.0.531.g2ccb3012c9-goog
