To be able to make some predictions of disk performance, it is useful to have a modelof storage allocation. Suppose that the disk is viewed as a linear address space ofN» 1 sectors, consisting of a run of data blocks, then a hole, then another run of datablocks, and so on. If empirical measurements show that the probability distributionsfor data and hole lengths are the same, with the chance of either being i sectors as 2-¹,what is the expected number of holes on the disk?

The expected number of holes on the disk is N/4. Explanation: The response given is appropriate.…

s, consisting of a run of data blocks, then a hole, then anothe so on. If empirical measurements show that the probability hole lengths are the same, with the chance of either being i s xpected number of holes on the disk?

s, consisting of a run of data blocks, then a hole, then anothe so on. If empirical measurements show that the probability hole lengths are the same, with the chance of either being i s xpected number of holes on the disk?

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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