Suppose that a disk drive has 5,000 cylinders, numbered 0 to 4,999. The drive is currently serving a request at cylinder 2,150, and the previous request was at cylinder 1,805. The queue of pending requests, in FIFO order, is: 2,069; 1,212; 2,296; 2,800; 544; 1,618; 356; 1,523; 4,965; 3,681 Starting from the current head position, what is the total distance (in cylinders) that the disk arm moves to satisfy all the pending requests for each of the following disk-scheduling algorithms? a. FCFS b. SCAN c. C-SCAN d. LOOK e. C-LOOK

Suppose that a disk drive has 5,000 cylinders, numbered 0 to 4,999. The drive is currently serving a request at cylinder 2,150, and the previous request was at cylinder 1,805. The queue of pending requests, in FIFO order, is: 2,069; 1,212; 2,296; 2,800; 544; 1,618; 356; 1,523; 4,965; 3,681 Starting from the current head position, what is the total distance (in cylinders) that the disk arm moves to satisfy all the pending requests for each of the following disk-scheduling algorithms? a. FCFS b. SCAN c. C-SCAN d. LOOK e. C-LOOK

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

See similar textbooks

Similar questions

Assume that there are the following processes in the deadline scheduler queue: Process Arrival Runtime Period Deadline 1 0 2 12 10 2 2 4 20 16 3 4 3 15 14 Complete the following schedule so each of the processes adheres to the deadline policy by replacing a dot with a process number (as necessary): TIME: 01234567890123456789012345678901234567890123456789 PROCESS: 112222333.......................................
The owner of KFC wants to use a system to record the orders for the hamburgers. KFC accept the orders via phone calls. When registered customers call KFC on the phone, they are asked their phone number. If the customer is not a registered customer, then a new record is created for the customer. When the phone number is typed into a computer, the name, the email address and the address of customer are automatically brought up on the screen. After taking the order, the total, including tax is calculated. Then the order is given to the cook. A receipt is printed. Sometimes, discount coupons are printed so the customer can get a discount. Carriers who make deliveries give customers a copy of the receipt and a coupon (if there is any). Weekly totals are kept for comparison with last month’s performance. 1.Write a summary of business activities for taking an order.. 2. Draw a context-level data flow diagram.. 3. Draw a level-0 data flow diagram..
The capacity of a cut is defined as the sum of capacities of nodes that composes the cut. O True O False
Consider a disk queue with requests for I/O to blocks on cylinders 47, 38, 121, 191, 87, 11, 92, 10. The C-LOOK scheduling algorithm is used. The head is initially at cylinder number 63, moving towards larger cylinder numbers on its servicing pass. The cylinders are numbered from 0 to 199. The total head movement (in number of cylinders) incurred while servicing these requests is
Given a directory tree of a file system, if /usr/jeff is the working directory, what is the absolute path name for the file whose relative path name is ../ast/z?
Consider the adjacency matrix below. Upload a picture (it can be hand drawn) of the adjacency list of the graph. Note: File size must not exceed 1 MB. * A B с D E A 0 1 0 1 0 B 1 0 1 0 0 C 1 0 1 0 0 1 D 1 0 0 1 E 0 0 1 0 0
Consider the adjacency matrix below. Upload a picture (it can be hand drawn) of the adjacency list of the graph. Note: File size must not exceed 1 MB. * A B с D E A 0 1 0 1 0 B 1 0 1 0 0 C 1 0 1 0 0 1 D 1 0 0 1 E 0 0 1 0 0
Subject: Operating Systems
Different algorithms are used for scheduling the disk head so that seek time may be reduced. Calculate a total number of heads movement for the following algorithms for the given numbers of disk cylinders. Shortest Seek Time First (SSTF) b) Circular Look (C-Look) Head Start: 71 Queue: 82 , 153 , 14 , 149 , 6 , 189 , 62 , 99 , 121
Student information is stored in a data area, and each student entry is formatted as follows:The first nine bytes are the student ID in ASCII format.The following byte is the course score.The following phrase is the section identifier. There are over 300 such student records in memory, which have been loaded consecutively beginning at address $10000. To indicate the conclusion of the records, the last record loaded is a dummy record with a section identifier of $FFFF. Create an assembler subroutine GetMax that searches the complete list for the highest mark. If there is a tie, the student with the highest score on the list should be found. The beginning address of the subroutine should be returned.
Answer the following questions about a scheduling system for assigning chefs to cooking slots. Within the system, every single chef and every single cooking slot is assigned an integer ID. These IDs start with 1 and increment by 1. That is, if there is a chef with ID equal to 6, there must be chefs with IDs equal to 1, 2, 3, 4 and 5. The same restriction applies to the cooking slot IDs. Note that any cooking slot not assigned a chef will be covered by Sara and her amazing cooking skills. \begin{enumerate} \item Consider the chefs with IDs ranging from $p$ to $q$ inclusive, where $p \leq q$, and consider the cooking slots with IDs ranging from $r$ to $s$ inclusive, where $r \leq s$. How many distinct functions for assigning these chefs to cooking slots are there? (The chefs are the domain and the cooking slots are the codomain.) \item Consider the chefs and cooking slots with IDs ranging from $p$ to $q$ inclusive, where $p \leq q$. How many distinct functions for assigning…
Assignment/Lab 9 In this lab, your task is to develop a simple address book tool. The tool maintains contact information of people. For each person, the tool maintains name and date of birth. Contact information consists of physical address and phone number. For physical addresses, the system must be able to maintain current and previous addresses. Current/active address information should have starting date and no end date, previous addresses must have a starting date and an ending date. A person cannot have multiple active physical address. For phone number, the system must maintain active phone numbers only, no previous phone numbers. For implementation, use MySQL database system. MySQL is open source and is available for Linux as well as Windows. For software application, use Python. The tool/application must support the following functionality: 1- Search current contact information by last name, the user enters last name, the system must locate active physical address and phone…