Metadata – Since there is a mapping between logical and physical location, the storage metadata and its management becomes key to a working reliable system.

元数据——由于有着逻辑与物理位置之间的映射关系，因此对于一个运行的可靠系统来说存储元数据的管理显得极为关键。

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For example, in the layout of physical-to-logical mapping shown in Figure 1, how could the user create a filesystem of, say 150gb, since the biggest disk is 80gb large?

例如，在图1所示的物理到逻辑映射布局中，最大的磁盘是80gb的，那么用户如何创建更大(比如150gb)的文件系统呢？

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The operations that may take longer with short extents include: finding extents, mapping logical to physical addresses, light scans, archives, read-ahead, and checkpoint flush.

可能由于短区段而增加操作时间的操作包括：查找区段、逻辑地址到物理地址的映射、轻量扫描、存档、预读、以及检查点刷新。

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