Consider a computer with 250 MB of available memory (not used by the OS), a mouse, a keyboard, and a printer. Three programs, Job1, Job2, and Job3, are submitted for execution at 5 seconds, 10 seconds, and 20 seconds, respectively. We assume minimal processor requirements for Job1 and Job2, and continuous printer use by Job2, and keyboard and mouse use by Jobl. In a simple batch environment, these jobs will be executed in sequence. Assuming Jobl completes in 10 seconds, Job2 must wait until the 10 seconds are over and then completes 15 seconds after that. Job3 begins after 30 seconds and completes at 35 seconds. Now, suppose that the jobs are run concurrently under a multiprogramming OS. The memory requirements for Job1, Job2, and Job3 are 100 Mb, 150 Mb, and 70 Mb, respectively.

Consider a computer with 250 MB of available memory (not used by the OS), a mouse, a keyboard, and a printer. Three programs, Job1, Job2, and Job3, are submitted for execution at 5 seconds, 10 seconds, and 20 seconds, respectively. We assume minimal processor requirements for Job1 and Job2, and continuous printer use by Job2, and keyboard and mouse use by Jobl. In a simple batch environment, these jobs will be executed in sequence. Assuming Jobl completes in 10 seconds, Job2 must wait until the 10 seconds are over and then completes 15 seconds after that. Job3 begins after 30 seconds and completes at 35 seconds. Now, suppose that the jobs are run concurrently under a multiprogramming OS. The memory requirements for Job1, Job2, and Job3 are 100 Mb, 150 Mb, and 70 Mb, respectively.

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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