Hi Chao,
On 2018/01/12 18:24, Chao Yu wrote:
Previously, our total node number (nat_bitmap) and total nat segment count
will not monotonously increase along with image size, and max nat_bitmap size
is limited by "CHECKSUM_OFFSET - sizeof(struct f2fs_checkpoint) + 1", it is
with bad scalability when user wants to create more inode/node in larger image.
So this patch tries to relieve the limitation, by default, limitting total nat
entry number with 20% of total block number.
Before:
image_size(GB) nat_bitmap sit_bitmap nat_segment sit_segment
16 3836 64 36 2
32 3836 64 72 2
64 3772 128 116 4
128 3708 192 114 6
256 3580 320 110 10
512 3260 640 100 20
1024 2684 1216 82 38
2048 1468 2432 44 76
4096 3900 4800 120 150
After:
image_size(GB) nat_bitmap sit_bitmap nat_segment sit_segment
16 256 64 8 2
32 512 64 16 2
64 960 128 30 4
128 1856 192 58 6
256 3712 320 116 10
512 7424 640 232 20
1024 14787 1216 462 38
2048 29504 2432 922 76
4096 59008 4800 1844 150
Signed-off-by: Chao Yu <yuchao0@...>
---
fsck/resize.c | 31 ++++++++++++++-----------------
include/f2fs_fs.h | 6 ++++--
mkfs/f2fs_format.c | 35 ++++++++++++++---------------------
3 files changed, 32 insertions(+), 40 deletions(-)
diff --git a/fsck/resize.c b/fsck/resize.c
index 143ad5d3c0a1..7613c7df4893 100644
--- a/fsck/resize.c
+++ b/fsck/resize.c
@@ -16,7 +16,7 @@ static int get_new_sb(struct f2fs_super_block *sb)
u_int32_t sit_segments, diff, total_meta_segments;
u_int32_t total_valid_blks_available;
u_int32_t sit_bitmap_size, max_sit_bitmap_size;
- u_int32_t max_nat_bitmap_size, max_nat_segments;
+ u_int32_t max_nat_bitmap_size;
u_int32_t segment_size_bytes = 1 << (get_sb(log_blocksize) +
get_sb(log_blocks_per_seg));
u_int32_t blks_per_seg = 1 << get_sb(log_blocks_per_seg);
@@ -47,7 +47,8 @@ static int get_new_sb(struct f2fs_super_block *sb)
get_sb(segment_count_sit))) * blks_per_seg;
blocks_for_nat = SIZE_ALIGN(total_valid_blks_available,
NAT_ENTRY_PER_BLOCK);
- set_sb(segment_count_nat, SEG_ALIGN(blocks_for_nat));
+ set_sb(segment_count_nat, SEG_ALIGN(blocks_for_nat) *
+ DEFAULT_NAT_ENTRY_RATIO / 100);
sit_bitmap_size = ((get_sb(segment_count_sit) / 2) <<
get_sb(log_blocks_per_seg)) / 8;
@@ -56,25 +57,21 @@ static int get_new_sb(struct f2fs_super_block *sb)
else
max_sit_bitmap_size = sit_bitmap_size;
- /*
- * It should be reserved minimum 1 segment for nat.
- * When sit is too large, we should expand cp area. It requires more
pages for cp.
- */
- if (max_sit_bitmap_size > MAX_SIT_BITMAP_SIZE_IN_CKPT) {
- max_nat_bitmap_size = CHECKSUM_OFFSET - sizeof(struct
f2fs_checkpoint) + 1;
- set_sb(cp_payload, F2FS_BLK_ALIGN(max_sit_bitmap_size));
+ max_nat_bitmap_size = (get_sb(segment_count_nat) <<
+ get_sb(log_blocks_per_seg)) / 8;
segment_count_nat would not exceed (CHECKSUM_OFFSET - sizeof(struct
f2fs_checkpoint) + 1) * 8 >> get_sb(log_blocks_per_seg) (align-down), I
think.
In my mind, the nat version bitmap is only located in cp page...
So segment_count_nat has a fixed up bound limitation...
+
+ set_sb(segment_count_nat, get_sb(segment_count_nat) * 2);
+
+ /* use cp_payload if free space of f2fs_checkpoint is not enough */
+ if (max_sit_bitmap_size + max_nat_bitmap_size >
+ MAX_BITMAP_SIZE_IN_CKPT) {
+ u_int32_t diff = max_sit_bitmap_size + max_nat_bitmap_size -
+ MAX_BITMAP_SIZE_IN_CKPT;
I looked up the f2fs source code, in __bitmap_ptr
if payload is used, the whole payload will be used for sit bitmap.
Therefore, I mean would it be u_int32_t diff = max_sit_bitmap_size?
or modify definition in f2fs.h?
+ set_sb(cp_payload, F2FS_BLK_ALIGN(diff));
} else {
- max_nat_bitmap_size = CHECKSUM_OFFSET - sizeof(struct
f2fs_checkpoint) + 1
- - max_sit_bitmap_size;
set_sb(cp_payload, 0);
}
- max_nat_segments = (max_nat_bitmap_size * 8) >>
- get_sb(log_blocks_per_seg);
-
- if (get_sb(segment_count_nat) > max_nat_segments)
- set_sb(segment_count_nat, max_nat_segments);
-
set_sb(segment_count_nat, get_sb(segment_count_nat) * 2);
set_sb(ssa_blkaddr, get_sb(nat_blkaddr) +
diff --git a/include/f2fs_fs.h b/include/f2fs_fs.h
index 4739085ed98f..77e53dfea474 100644
--- a/include/f2fs_fs.h
+++ b/include/f2fs_fs.h
@@ -657,8 +657,8 @@ struct f2fs_checkpoint {
unsigned char sit_nat_version_bitmap[1];
} __attribute__((packed));
-#define MAX_SIT_BITMAP_SIZE_IN_CKPT \
- (CHECKSUM_OFFSET - sizeof(struct f2fs_checkpoint) + 1 - 64)
+#define MAX_BITMAP_SIZE_IN_CKPT \
+ (CHECKSUM_OFFSET - sizeof(struct f2fs_checkpoint) + 1)
/*
* For orphan inode management
@@ -846,6 +846,8 @@ struct f2fs_node {
#define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
#define NAT_BLOCK_OFFSET(start_nid) (start_nid / NAT_ENTRY_PER_BLOCK)
+#define DEFAULT_NAT_ENTRY_RATIO 20
+
#ifdef ANDROID_WINDOWS_HOST
#pragma pack(1)
#endif
diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
index a13000184300..90363370031e 100644
--- a/mkfs/f2fs_format.c
+++ b/mkfs/f2fs_format.c
@@ -157,7 +157,7 @@ static int f2fs_prepare_super_block(void)
u_int64_t zone_align_start_offset, diff;
u_int64_t total_meta_zones, total_meta_segments;
u_int32_t sit_bitmap_size, max_sit_bitmap_size;
- u_int32_t max_nat_bitmap_size, max_nat_segments;
+ u_int32_t max_nat_bitmap_size;
u_int32_t total_zones;
u_int32_t next_ino;
enum quota_type qtype;
@@ -272,7 +272,8 @@ static int f2fs_prepare_super_block(void)
blocks_for_nat = SIZE_ALIGN(total_valid_blks_available,
NAT_ENTRY_PER_BLOCK);
- set_sb(segment_count_nat, SEG_ALIGN(blocks_for_nat));
+ set_sb(segment_count_nat, SEG_ALIGN(blocks_for_nat) *
+ DEFAULT_NAT_ENTRY_RATIO / 100);
/*
* The number of node segments should not be exceeded a "Threshold".
* This number resizes NAT bitmap area in a CP page.
@@ -286,29 +287,21 @@ static int f2fs_prepare_super_block(void)
else
max_sit_bitmap_size = sit_bitmap_size;
- /*
- * It should be reserved minimum 1 segment for nat.
- * When sit is too large, we should expand cp area. It requires more
- * pages for cp.
- */
- if (max_sit_bitmap_size > MAX_SIT_BITMAP_SIZE_IN_CKPT) {
- max_nat_bitmap_size = CHECKSUM_OFFSET -
- sizeof(struct f2fs_checkpoint) + 1;
- set_sb(cp_payload, F2FS_BLK_ALIGN(max_sit_bitmap_size));
+ max_nat_bitmap_size = (get_sb(segment_count_nat) <<
+ log_blks_per_seg) / 8;
+
+ set_sb(segment_count_nat, get_sb(segment_count_nat) * 2);
+
+ /* use cp_payload if free space of f2fs_checkpoint is not enough */
+ if (max_sit_bitmap_size + max_nat_bitmap_size >
+ MAX_BITMAP_SIZE_IN_CKPT) {
+ u_int32_t diff = max_sit_bitmap_size + max_nat_bitmap_size -
+ MAX_BITMAP_SIZE_IN_CKPT;
The same as above. :)
Thanks,
+ set_sb(cp_payload, F2FS_BLK_ALIGN(diff));
} else {
- max_nat_bitmap_size =
- CHECKSUM_OFFSET - sizeof(struct f2fs_checkpoint) + 1
- - max_sit_bitmap_size;
set_sb(cp_payload, 0);
}
- max_nat_segments = (max_nat_bitmap_size * 8) >> log_blks_per_seg;
-
- if (get_sb(segment_count_nat) > max_nat_segments)
- set_sb(segment_count_nat, max_nat_segments);
-
- set_sb(segment_count_nat, get_sb(segment_count_nat) * 2);
-
set_sb(ssa_blkaddr, get_sb(nat_blkaddr) + get_sb(segment_count_nat) *
c.blks_per_seg);
--
2.15.0.55.gc2ece9dc4de6
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