操作系统导论习题解答（10. Multi-CPU Scheduling）

Homework (Simulation)

In this homework, we’ll use multi.py to simulate a multi-processor CPU scheduler, and learn about some of its details. Read the related README for more information about the simulator and its options.

Question & Answer

1. To start things off, let’s learn how to use the simulator to study how to build an effective multi-processor scheduler. The first simulation will run just one job, which has a run-time of 30, and a working-set size of 200. Run this job (called job ’a’ here) on one simulated CPU as follows: ./multi.py -n 1 -L a:30:200. How long will it take to complete? Turn on the -c flag to see a final answer, and the -t flag to see a tick-by-tick trace of the job and how it is scheduled.

2. Now increase the cache size so as to make the job’s working set (size=200) fit into the cache (which, by default, is size=100); for example, run ./multi.py -n 1 -L a:30:200 -M 300. Can you predict how fast the job will run once it fits in cache? (hint: