number of sectors per track is 100. Thec timefrom 0 to 99 rotating at 3000 rpm. TheConsider a desk with the 100 tracks umberedto move the head between two successive(a) Consider a set of disk roquests to read(b) Consider an initial set of 100 arbitrarytracks is 02 millisecondsdata from tracks 32. 7, 45, 5 and 10Assuming that the elevator algorithm isused to schedule disk requests and thehead is initially at track 25 moving up(towards larger track numbers), What isthe total seck time for servicing therequests?disk requests and assume that no new direquests arrive while servicing theseroquests. If the head is initially at track 0and the elevator algorithm is used toschedule disk requests, what is the worstcase time to complete all the requests?

Given: A Disk with the 100 tracks numbered from 0 to 99 rotating at 3000 rpm. Number of sector per…

Consider a disk with the 100 tracks Bumbered from 0 to 99 rotating at 3000 rpm The to mave the head between two successive (a) Consider a set of disk requests to read head is initially at track 25 moving up aumber of sectors per track is 100. The ti tracks is 02 milliseconds data from tracks 32, 7, 45, 5 and 10 Assuming that the elevator algorithm is used to schedule disk requests and the (lowards larger track numbers), What is the total seck time for servicing the requests? (b) Consider an initial set of 100 arbitrary disk requests and assume that no new disk requests arrive while servicing these roquests. If the head is initially at track 0 and the elevator algorithm is used to schedule disk requests, what ss the worst case time to complete all the requests?

Consider a disk with the 100 tracks Bumbered from 0 to 99 rotating at 3000 rpm The to mave the head between two successive (a) Consider a set of disk requests to read head is initially at track 25 moving up aumber of sectors per track is 100. The ti tracks is 02 milliseconds data from tracks 32, 7, 45, 5 and 10 Assuming that the elevator algorithm is used to schedule disk requests and the (lowards larger track numbers), What is the total seck time for servicing the requests? (b) Consider an initial set of 100 arbitrary disk requests and assume that no new disk requests arrive while servicing these roquests. If the head is initially at track 0 and the elevator algorithm is used to schedule disk requests, what ss the worst case time to complete all the requests?

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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