PPT-A Case for Redundant Arrays of Inexpensive Disks (RAID)

David A Patterson Garth Gibson and Randy H Katz Presented by Connor Bolton Background 1974 to 1984 Single chip speed increased 40 a year Magnetic disk doubled capacity and halved in price every 3 years. The first implementations of RAID in 1990 were very expensive controller boards with high rmance IO processors that were as powerful as the host CPU At that time when hardwarebased RAID solutions were the only option the cost of a RAID controller li Clare O’Brien . WWII in the Pacific . The Main Players. Vice Admiral Halsey of the . U.S.S. Enterprise . Lieutenant Colonel . James Doolittle . Captain Marc Mitscher of the . U.S.S. Hornet. In response to the shock and anger following Pearl Harbor. RAID. What is RAID. ?. RAID is an acronym for Redundant Array of Independent Drives (or Disks), also known as Redundant Array of Inexpensive Drives (or Disks). The various types of RAID are data storage schemes that divide and/or replicate data among multiple hard drives. Hai. Lu. RAID. RAID. , an acronym for . redundant array of independent disks. or also known as . redundant array of inexpensive disks. , is a technology that allows high levels of storage reliability from low-cost and less reliable PC-class disk-drive components, via the technique of arranging the devices into arrays for redundancy.. RAID (Redundant Arrays of Independent Disks). Disk . organization technique that manages a large number of disks, providing a view of a single disk of. High capacity and high speed up using multiple disk in parallel. 1. Readings. Chapter . 10. 2. Long-term Information Storage. Three essential requirements:. Must store large amounts of data. Information stored must survive the termination of the process using it (. Lecture 39: IO Disks. Instructor: Dan Garcia. http://inst.eecs.Berkeley.edu/~cs61c/. 1. Technology in the News. www.cnn.com/2014/04/28/tech/innovation/google-self-driving-car/. 2. Review. . Exceptions are “Unexpected” events. Case Study: Facebook f4. Steve Ko. Computer Sciences and Engineering. University at Buffalo. Recap. Engineering principle. Make the common case fast, and rare cases correct. Power law. Haystack. A design for warm photos. A disk subsystem is a hard disk server.. Servers are connected to the . connection port . of the subsystem using standard I/O techniques such as SCSI, . fibre. channel etc.. The internal structure of the disk subsystem is completely hidden from the server. The server sees on the hard disks. . AZIMUTH READOUT. Challenge. Paul Wade W1GHZ. Digital Electronic Protractor. 0 . to 360°. $16.95. i. gaging.com. Adaptable for Portable Microwave. but. What about Remote Readout?. Inexpensive digital levels have been hacked for remote readout. and RAID. Outline. Disks. Disk scheduling algorithms. Redundancy in storage . systems, RAID. 2. Disk Geometry. Disks have multiple platters. Each platter has . an arm and a head for accessing data. The arms for the different platters move together. Web Content Distribution-. --3. Case Study: Facebook f4. Steve Ko. Computer Sciences and Engineering. University at Buffalo. Recap. Engineering principle. Make the common case fast, and rare cases correct. Two main types: Magnetic and Optical. Random access to memory. The hardware must be controlled by driver software called the “controller” in order to be used. Hard Disks, RAID, and Error Handling. Chapter 8 Adding Disks Loops Run instructions again, and again, and again…. Check some condition If true, repeat 2 types of loops for loop while loop First, the variable used in loop condition must be initialized, then execution of the loop begins.