细分和分页硬件
下图说明了分割的硬件实现：
分页的硬件实现也如下所示：
来源：来源：操作系统概念教科书 正如我们所看到的那样，两个内存方案都在其逻辑地址定义中使用偏移。在分割中，我们始终检查此偏移量是否小于片段的限制（大小），如果偏移量大于段的限制，则我们将陷阱陷入操作系统（地址错误）。但是，该检查在分页硬件中不可用，尽管它在物理地址中也使用偏移？这是为什么 ？这是否意味着在第2页中，我们始终保证不能进行“未经授权”的内存访问（例如，内存访问另一个过程的地址空间）？
The below figure illustrates the hardware implementation of segmentation :
The hardware implementation of paging is also shown below :
Source: Operating system concepts textbook
As we can see that both memory schemes use offsets in their logical address definition. In segmentation, we always check that this offset is less than the limit ( size ) of the segment, if the offset is larger than the limit of the segment, then we trap to the operating system ( addressing error ). However, this check is not available in paging hardware, although it also uses offset in its physical address? Why is that ? Does this mean that in paging we always guarantee that no "unauthorized" memory access can be made ( for example memory access to another process's address space ) ?
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