This space is used if a block in the original file system changes.

如果原始文件系统中的一个数据块发生更改，就会使用此空间。

youdao

Once created, global backups persist as long as original memory block.

一旦被建立，全局备份会和当前数据持续同样长的时间。

youdao

Once created, global backups persist as long as original memory block.

一旦被建立，全局备份会和当前数据持续同样长的时间。

youdao