根据dump的结果，在word里面画了一个非常简单的示意图，每个数据文件最前面的8个块，是LMT用于管理extent分配的。
更详细的文档可以参考itpub电子杂志internal专刊中piner关于LMT和ASSM的文章。
数据文件（LMT+ASSM）（每格为1个block，block size为8k）
FIRST LEVEL BITMAP BLOCK
SECOND LEVEL BITMAP BLOCK
PAGETABLE SEGMENT HEADER
Data Block
Data Block
Data Block
Data Block
Data Block
FIRST LEVEL BITMAP BLOCK
SECOND LEVEL BITMAP BLOCK
PAGETABLE SEGMENT HEADER
Data Block
Data Block
Data Block
Data Block
Data Block
FIRST LEVEL BITMAP BLOCK
SECOND LEVEL BITMAP BLOCK
PAGETABLE SEGMENT HEADER
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
FIRST LEVEL BITMAP BLOCK
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
数据文件（LMT）（每格为1个block，block size为8k）
DATA SEGMENT HEADER - UNLIMITED
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
DATA SEGMENT HEADER - UNLIMITED
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
DATA SEGMENT HEADER - UNLIMITED
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block
Data Block