23.12.2020 06:48, Chris Murphy пишет:
> Hi,
> 
> kernel is 5.10.2
> 
> cp --reflink hi hi2
> 
> This results in two EXTENT_DATA items with different offsets,
> therefore I think the data is duplicated in the leaf? Correct? Is it
> expected?
> 

I'd say yes. Inline data is contained in EXTEND_DATA item and
EXTENT_DATA item cannot be shared by two different inodes (it is keyed
by inode number).

Even when cloning regular extent you will have two independent
EXTENT_DATA items pointing to the same physical extent.

>         item 9 key (257 EXTENT_DATA 0) itemoff 15673 itemsize 53
>                 generation 435179 type 0 (inline)
>                 inline extent data size 32 ram_bytes 174 compression 3 (zstd)
> 
> ...
>         item 13 key (258 EXTENT_DATA 0) itemoff 15364 itemsize 53
>                 generation 435179 type 0 (inline)
>                 inline extent data size 32 ram_bytes 174 compression 3 (zstd)
> 
> 
> The entire file tree containing only these two files follows:
> 
> 
> file tree key (394 ROOT_ITEM 0)
> leaf 26442252288 items 14 free space 15014 generation 435212 owner 394
> leaf 26442252288 flags 0x1(WRITTEN) backref revision 1
>         item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160
>                 generation 435123 transid 435212 size 10 nbytes 0
>                 block group 0 mode 40755 links 1 uid 1000 gid 1000
> rdev 0
>                 sequence 5267 flags 0x0(none)
>                 atime 1608689569.708325037 (2020-12-22 19:12:49)
>                 ctime 1608694856.721370147 (2020-12-22 20:40:56)
>                 mtime 1608694856.721370147 (2020-12-22 20:40:56)
>                 otime 1608689569.708325037 (2020-12-22 19:12:49)
>         item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12
>                 index 0 namelen 2 name: ..
>         item 2 key (256 DIR_ITEM 432062026) itemoff 16079 itemsize 32
>                 location key (257 INODE_ITEM 0) type FILE
>                 transid 435124 data_len 0 name_len 2
>                 name: hi
>         item 3 key (256 DIR_ITEM 4216900732) itemoff 16046 itemsize 33
>                 location key (258 INODE_ITEM 0) type FILE
>                 transid 435196 data_len 0 name_len 3
>                 name: hi2
>         item 4 key (256 DIR_INDEX 2) itemoff 16014 itemsize 32
>                 location key (257 INODE_ITEM 0) type FILE
>                 transid 435124 data_len 0 name_len 2
>                 name: hi
>         item 5 key (256 DIR_INDEX 4) itemoff 15981 itemsize 33
>                 location key (258 INODE_ITEM 0) type FILE
>                 transid 435196 data_len 0 name_len 3
>                 name: hi2
>         item 6 key (257 INODE_ITEM 0) itemoff 15821 itemsize 160
>                 generation 435124 transid 435212 size 174 nbytes 174
>                 block group 0 mode 100644 links 1 uid 1000 gid 1000
> rdev 0
>                 sequence 19 flags 0x0(none)
>                 atime 1608689574.394444809 (2020-12-22 19:12:54)
>                 ctime 1608694856.721370147 (2020-12-22 20:40:56)
>                 mtime 1608692923.231038818 (2020-12-22 20:08:43)
>                 otime 1608689574.394444809 (2020-12-22 19:12:54)
>         item 7 key (257 INODE_REF 256) itemoff 15809 itemsize 12
>                 index 2 namelen 2 name: hi
>         item 8 key (257 XATTR_ITEM 3817753667) itemoff 15726 itemsize 83
>                 location key (0 UNKNOWN.0 0) type XATTR
>                 transid 435124 data_len 37 name_len 16
>                 name: security.selinux
>                 data unconfined_u:object_r:unlabeled_t:s0
>         item 9 key (257 EXTENT_DATA 0) itemoff 15673 itemsize 53
>                 generation 435179 type 0 (inline)
>                 inline extent data size 32 ram_bytes 174 compression 3 (zstd)
>         item 10 key (258 INODE_ITEM 0) itemoff 15513 itemsize 160
>                 generation 435196 transid 435196 size 174 nbytes 174
>                 block group 0 mode 100644 links 1 uid 1000 gid 1000 rdev 0
>                 sequence 34 flags 0x0(none)
>                 atime 1608693921.97510335 (2020-12-22 20:25:21)
>                 ctime 1608693921.97510335 (2020-12-22 20:25:21)
>                 mtime 1608693921.97510335 (2020-12-22 20:25:21)
>                 otime 1608693921.97510335 (2020-12-22 20:25:21)
>         item 11 key (258 INODE_REF 256) itemoff 15500 itemsize 13
>                 index 4 namelen 3 name: hi2
>         item 12 key (258 XATTR_ITEM 3817753667) itemoff 15417 itemsize 83
>                 location key (0 UNKNOWN.0 0) type XATTR
>                 transid 435196 data_len 37 name_len 16
>                 name: security.selinux
>                 data unconfined_u:object_r:unlabeled_t:s0
>         item 13 key (258 EXTENT_DATA 0) itemoff 15364 itemsize 53
>                 generation 435179 type 0 (inline)
>                 inline extent data size 32 ram_bytes 174 compression 3 (zstd)
> total bytes 31005392896
> bytes used 20153282560
> 
> 
> 

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