Reverse mapping, or RMAP, was implemented in the 2.5 kernel to solve this problem.

反向映射，或者说是RMAP，就是为解决此问题而在2.5内核中实现的。

youdao

Despite this, the performance of the rmap patch — especially on high-end systems and under heavy loads — is significantly better than the 2.4 kernel's VM system.

尽管如此，rmap的性能——尤其是处于高负载的高端系统——相对于2.4内核的虚拟内存系统还是有了显著的提高。

youdao

Since this wait queue is used sparsely, a smaller wait queue implementation using hash queues to find the correct wait queue has been implemented in the rmap patch.

因为这个等待队列极少用到，所以在 rmap 补丁中实现了一个更小的队列，通过哈希队列来找到正确的等待队列。

youdao