What is the . Let us define “most-recently-used” (MRU) as a page removal algorithm that removes from memory the most recently used page. Perform a page trace analysis using three page frames and the page requests from the previous exercise. Compute the failure and success ratios and explain why you think MRU is, or is not, a viable memory allocation system
Just a gut feeling, I'd say it is not. The MRU page is likely to be the next page accessed, don't you think? Swapping it out is likely to be a waste of time.
Let us define “most-recently-used” (MRU) as a page removal algorithm that
removes from memory the most recently used page. Perform a page trace
analysis using three page frames and the page requests from the previous exercise. Compute the failure and success ratios and explain why you think MRU
is, or is not, a viable memory allocation system.
To analyze the page trace using the Most-Recently-Used (MRU) algorithm with three page frames, we need the page requests from the previous exercise. Please provide the page requests to proceed.
To perform a page trace analysis using the most-recently-used (MRU) algorithm, you need to have the page requests from the previous exercise. Once you have those, you can follow these steps:
1. Start with three empty page frames (assuming you have three available in this case).
2. Go through the page requests one by one. When a page is requested, check if it is already present in any of the page frames.
3. If the requested page is already present in a page frame, remove it from its current position and move it to the front of the page frame list since it is the most recently used.
4. If the requested page is not present in a page frame, you need to replace a page using the MRU algorithm. Remove the page from the end of the page frame list since it is the oldest used page, and insert the new requested page at the front of the list.
5. Continue this process until you have processed all the page requests.
To compute the failure and success ratios, you need to count the number of page faults (when a requested page is not found in any of the page frames) and the number of successful page hits (when a requested page is found in a page frame).
Once you have these counts, you can calculate the ratios:
- Failure Ratio = Number of Page Faults / Total Number of Page Requests
- Success Ratio = Number of Page Hits / Total Number of Page Requests
To assess whether the MRU algorithm is a viable memory allocation system, you need to consider its pros and cons:
Pros:
- The MRU algorithm can be simple to implement and understand.
- It prioritizes recently used pages, which can be beneficial for certain types of workloads where locality of reference is important.
- It may perform well for certain applications that exhibit temporal locality, where recently accessed pages are likely to be accessed again soon.
Cons:
- The MRU algorithm does not take into account the frequency of page accesses. Even if a page was recently accessed, if it is not accessed frequently, keeping it in memory may not be optimal.
- It may not work well for workloads with poor temporal locality, where pages accessed in the past are unlikely to be accessed again in the near future.
- It can be sensitive to the order of page requests, as the MRU list needs to be updated for every page request.
Considering these pros and cons, it is important to analyze the specific workload and characteristics of the system to determine whether the MRU algorithm is a viable memory allocation system.