P3L5 Flashcards Preview

CS6200 Final > P3L5 > Flashcards

Flashcards in P3L5 Deck (16):
1

I/O 3 Facts

1. Have protocols
2. Have dedicated handlers
3. Decouple I/O details from core processing

2

Microcontroller

Device's CPU

3

Command Registers

-Command
-Data transfers
-Status

4

PCI

Peripheral Component Interconnect

5

Character device

get/put character

6

BAR

Base Address Registers

7

Memory Mapped IO

Part of host physical memory dedicated for device interactions

8

IO Port Model

Dedicated in/out instructions fro device access

9

PIO

Programmed I/O
- No additional hw support needed
- CPU programs device via command registers

10

DMA

Direct Memory Access
- 2 CPU instructions, but 1 is complex
- Data must be in physical memory (Pinned)

11

Typical Device Access

- system call
- in-kernel stack
- driver invocation
- device request configuration
- device performs request

12

indoe

persistent representation of file "index"
list of all data blocks

13

dentry

directory entry

14

superblock

filesystem-specific information regarding the FS layout

15

superblock contents

inode blocks
data blocks
free blocks

16

Direct Access Optimizations

Caching/Buffering
I/O Scheduling
Prefetching
Journaling/Logging