Copyright © 2006 Keio University
Computer ArchitectureComputer ArchitectureLecture 6: Lecture 6: Basics of I/O and Storage SystemsRodney Van MeterRodney Van Meter2009/11/102009/11/[email protected]@sfc.wide.ad.jphttp://www.sfc.wide.ad.jp/aqua/http://www.sfc.wide.ad.jp/aqua/
Platter, Spindle, Arm, and Head
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Revised Class Schedule
• 第 6 回 11月 10日 入出力Lecture 6, November 10: Basics of I/O and Storage Systems
• 11月 17日 休講November 17: No class!
• 11月 24日 休講November 24: No class! (ORF! Please come.)
• 第 7 回 12月 1 日 プロセッサー:パイプラインの基本Lecture 7, December 1: Processors: Basics of Pipelining
• 第 8 回 12月 8 日 メモリ:キャッシュLecture 8, December 8: Memory: Caching and Memory Hierarchy
• 第 9 回 12月 12日(土曜日!) メモリ:仮想記録Lecture 9, December 12 (Saturday!): Memory: Virtual Memory
• 第 10回 12月 15日 Lecture 10, December 15: Systems: Shared-Memory Multiprocessors
• 第 11回 12月 22日 Lecture 11, December 15: Systems: Distributed-Memory Multiprocessors and Interconnection Networks
• 第 12回 1 月 12日 RAID: ストレージの並列と安全性Lecture 12, January 12: RAID: Parallelism and Protection in Storage Systems
• 第 13回 1 月 19日 Lecture 13, January 19: The Future and the Past: Review
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Outline• What's a Disk Drive?
• The Importance of a Disk Drive• The Insides of a Disk Drive• The Access Time Gap• Disk Drive Trends• A Little History• The Basics of a Bus• Homework
What’s a Disk Drive?
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What’s Important About a Disk Drive?
• Expensive• Consume lots of power• Performance bottleneck• Fragile
But they hold your data without power (they are nonvolatile), for a long time! Lots and lots of data!
Moore’s Law
Growth of Capacity Over Two Decades
Global Disk Shipments (in TB)
What’s a Disk Drive?
Anatomy of a Hard Drive
The Platter(s)
The Platters: 3 Disks, 6 Arms & Heads
Platter, Spindle, Arm, and Head
Arm, Slider & Read/Write Head
The Head on the Slider
Magnetic Media & R/W Head
Cyclinder, Head, Sector (CHS)
Video: Arm Moving
Video courtesy of Jun Takei, Intel
Video: Arm Moving (2)
Video courtesy of Jun Takei, Intel
Growth of Capacity Over Two Decades
Transfer Rate
Access Time Gap
A Little History: The RAMAC
A Little History: The RAMAC
RAMAC Delivery!
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Bus
• Shared bandwidth• Requires addressing• Transactions• Arbitration: priority, fairness• Limitations: width, length (capacitance, 電気容量 )• Types: memory, peripheral• Standardization
Buses: System Diagram
Buses: System Diagram
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Homework
• 1. Add a new type of disk drive to the table available on my web page.
• 2. For your drive, calculate:– A. How long to read entire disk sequentially?– B. How long to read the whole thing in random order, 512 bytes at a time?
• 3. Tell me who controls the specification for each of the following buses:– A. Frontside bus– B. Memory bus– C. PCI– D. SCSI