IO Management and Disk Scheduling

Categories of I/O Devices

Categories of I/O Devices

Categories of I/O Devices

Differences in I/O Devices

Differences in I/O Devices

Techniques for Performing I/O

Techniques for Performing I/O

Operating System Design Objectives

Operating System Design Objectives

A Model of I/O Organization

I/O Buffering

I/O Buffering

No Buffering

Single Buffer

Single Buffer

Single Buffer

Double Buffer

Circular Buffer

Disk Performance Parameters

Disk Performance Parameters

Disk Scheduling Policies

Disk Scheduling Policies

Disk Scheduling Policies

Disk Scheduling Policies

Disk Scheduling Policies

Disk Scheduling Policies

Disk Scheduling Policies

Disk Scheduling Policies

RAID 0 (non-redundant)

Data Mapping for RAID Level 0 Array

RAID 1 (mirrored)

RAID 2 (redundancy through Hamming code)

RAID 3 (bit-interleaved parity)

RAID 4 (block-level parity)

RAID 5 (block-level distributed parity)