Ben Kero
Clint Whiteside
Michael Johnson
CS411 Group 11
Project 4 Plan

For this project we have been asked to implement a LOOK I/O scheduler. The LOOK scheduler is an elevator scheduler, that is it orders operations by location and moves across the disk to service requests in a linear fashion. Once the head has reached the "end" of the disk it reverses, servicing requests in a similar manner. This is opposed to the no-op scheduler we are modifying which is First Come First Serve, essentially seeking the head for every operation without regard to physical location.

Below is a summary of the required code additions/changes that we have identified:

Config:
    Add CONFIG_IOSCHED_CLOCK option.

    Copy a bunch of noop code into clock then:
        Make look_data datastructure with:
                queue pointer to next

                Add a look_merged_request function to delete the init of the list.

                Take noop_dispatch and modify it to use our pointer to the next request to dispatch.

                Then write an IO tester that benchmarks how well the scheduler works, and compare it against the noop scheduler.

                Add a look_insert_request function to take an IO request and insert it into our queue.