出生/crtime 时间戳记录在一个 xfs 上，但不记录在另一个 xfs 文件系统上

Question

两个不同的 Fedora 上的两个不同的 xfs 文件系统。

1. 为什么其中一个在 inode 中记录了 Birth(crtime) 而另一个却没有？
2. 如何查找两个文件系统之间的配置/属性差异？

#1 XFS v5（Fedora 30）：

# stat tea.txt 
File: tea.txt
Size: 0             Blocks: 0          IO Block: 4096   regular empty file
Device: fd01h/64769d    Inode: 17477205    Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/    root)
Context: unconfined_u:object_r:admin_home_t:s0
Access: 2020-06-29 20:49:05.667633345 +0100
Modify: 2020-06-29 20:49:05.667633345 +0100
Change: 2020-06-29 20:49:05.667633345 +0100
Birth: 2020-06-29 20:49:05.667633345 +0100

xfs_db> version
versionnum [0xb4b5+0x18a] = V5,NLINK,DIRV2,ATTR,ALIGN,LOGV2,EXTFLG,MOREBITS,ATTR2,LAZYSBCOUNT,PROJID32BIT,CRC,FTYPE,FINOBT

# xfs_info /dev/sda1
meta-data=/dev/sda1 isize=512    agcount=5, agsize=1376256 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=0, rmapbt=0
         =                       reflink=0
data     =                       bsize=4096   blocks=6291456, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=2688, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

#2 XFS v5（Fedora 32）：

# stat tea2.txt
File: tea2.txt
Size: 0             Blocks: 0          IO Block: 4096   regular empty file
Device: 700h/1792d  Inode: 132         Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/    root)
Context: unconfined_u:object_r:unlabeled_t:s0
Access: 2020-06-29 20:59:26.855416418 +0100
Modify: 2020-06-29 20:59:26.855416418 +0100
Change: 2020-06-29 20:59:26.855416418 +0100
Birth: -
        
xfs_db> version
versionnum [0xb4b5+0x18a] = V5,NLINK,DIRV2,ATTR,ALIGN,LOGV2,EXTFLG,MOREBITS,ATTR2,LAZYSBCOUNT,PROJID32BIT,CRC,FTYPE,FINOBT
    
# xfs_info /dev/sda1
meta-data=/dev/sda1              isize=512    agcount=4, agsize=11796480 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=0, rmapbt=0
         =                       reflink=0
data     =                       bsize=4096   blocks=47185920, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=23040, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0