Page faults rise. But the issue is non trivial. Hence some processors are now supporting multiple page sizes. Typically, each process has its own segment table See Figure 8. To combine their advantages some processors and OS page the segments.
Several combinations exists.
Operating System Software n Memory management software depends on whether the hardware supports paging or segmentation or both n Pure segmentation systems are rare. To achieve good performance we need a low page fault rate Fetch Policy n Determines when a page should be brought into main memory. This would require expensive hardware and a great deal of overhead. Consequently very few computer systems provide sufficient hardware support for true LRU replacement policy n Other algorithms are used instead The FIFO Policy n Treats page frames allocated to a process as a circular buffer - When the buffer is full, the oldest page is replaced. When it is time to replace a page, the first frame encountered with the use bit set to 0 is replaced.