Princess Sumaya Univ. Computer Engineering Dept. Chapter 6: Chapter 6:
Mar 29, 2015
Princess Sumaya Univ.Computer Engineering Dept.
Chapter 6:Chapter 6:
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
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I/O ConnectionI/O Connection
MainMemory
Interrupts
Memory I/O InterconnectMemory I/O Interconnect
CacheCache
ProcessorProcessor
I/OI/OControllerController
I/OI/OControllerController
I/OI/OControllerController
Disk DiskNetworkNetworkI/OI/O
DevicesDevices
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Magnetic DiskMagnetic Disk
Nonvolatile
Tracks & Sectors
Recorded Information
● Sector Number, Gap, Data, ECC, Gap, Next Sector Num.
Rotational Latency
● 5400 RPM (½ rotation / 5400) = 5.6 ms
Transfer Time
● Sector: ≈ 100 MB/s
● Cache: ≈ 375 MB/s = 3 Gbps SATA-2
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Disk InterfaceDisk Interface
Advanced Technology Attachment
● SATA (Serial)
Small Computer Systems Interface
● SCSI (Parallel)
● SAS (Serial Attached SCSI)
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
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Flash StorageFlash Storage
Semiconductor
● Non Volatile (EEPROM)
● Faster, Smaller and Lower Power
● Higher Cost
● Block R/W
● Wearout (10,000 ~ 100,000 Writes per Cell)
● Wear Leveling (Remap Blocks)
Solid State Disk (SSD)
Hybrid Hard Disk
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
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BussesBusses
Processor-Memory Bus
● Short, High Speed and Matched Width
I/O Bus
● Can be Lengthy and Connect Many Types
● Often Have a Wide Range Bandwidth
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I/O TransactionI/O Transaction
Two Parts● Sending Memory Address
● Sending or Receiving Data
Synchronous● All Devices on the Bus Run on the Same Clock Rate
● Clock Skew Limits Length
Asynchronous● External: Firewire, USB, etc.
● Internal: PCI Express, SATA, etc.
Handshaking
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
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Parallelism & I/OParallelism & I/O
Redundant Array of Inexpensive Disks (RAID)
● RAID 0 Striping
BLK 0
BLK 2
BLK 4
BLK 6
BLK 1
BLK 3
BLK 5
BLK 7
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
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Parallelism & I/OParallelism & I/O
Redundant Array of Inexpensive Disks (RAID)
● RAID 0 Striping
● RAID 1 MirroringBLK 0
BLK 1
BLK 2
BLK 3
BLK 0
BLK 1
BLK 2
BLK 3
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
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Parallelism & I/OParallelism & I/O
Redundant Array of Inexpensive Disks (RAID)
● RAID 0 Striping
● RAID 1 Mirroring
● RAID 2 Error Detection & Correction Code
Bit 0
Bit 2
Bit 4
Bit 6
Bit 1
Bit 3
Bit 5
Bit 7
Parity
Parity
Parity
Parity
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
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Parallelism & I/OParallelism & I/O
Redundant Array of Inexpensive Disks (RAID)
● RAID 0 Striping
● RAID 1 Mirroring
● RAID 2 Error Detection & Correction Code
● RAID 3 Bit-Interleaved Parity
Byte 0
Byte 2
Byte 4
Byte 6
Byte 1
Byte 3
Byte 5
Byte 7
Parity
Parity
Parity
Parity
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
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Parallelism & I/OParallelism & I/O
Redundant Array of Inexpensive Disks (RAID)
● RAID 0 Striping
● RAID 1 Mirroring
● RAID 2 Error Detection & Correction Code
● RAID 3 Bit-Interleaved Parity
● RAID 4 Block-Interleaved Parity
BLK 0
BLK 2
BLK 4
BLK 6
BLK 1
BLK 3
BLK 5
BLK 7
Parity
Parity
Parity
Parity
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
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Parallelism & I/OParallelism & I/O
Redundant Array of Inexpensive Disks (RAID)
● RAID 0 Striping
● RAID 1 Mirroring
● RAID 2 Error Detection & Correction Code
● RAID 3 Bit-Interleaved Parity
● RAID 4 Block-Interleaved Parity
● RAID 5 Distributed Block- Interleaved Parity
BLK 0
BLK 2
Parity
BLK 6
BLK 1
Parity
BLK 4
BLK 7
Parity
BLK 3
BLK 5
Parity
Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.Princess Sumaya University 22540 – Computer Arch. & Org (2) Computer Engineering Dept.
Chapter 6Chapter 6