PPT-RAID Redundant Array of Inexpensive (Independent) Disks

Use multiple smaller disks cf one large disk Parallelism improves performance Plus extra disks for redundant data storage Provides fault tolerant storage system Especially if failed disks can be hot swapped. 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 P ATTERSON G ARTH IBSON AND ANDY H K ATZ Computer Science Division Department of Electrical Engineering and Computer Sciences 571 Evans Hall University of California Berkeley CA 94720 Abstract Increasing performance of CPUs and memories will be squa !. What. is an air raid?. Where. did they happen?. How. did people protect themselves?. What. did the government do?. What is an air raid?. BACK. Each night, . signal planes dropped incendiary bombs (or fire bombs) . . . We . have all heard someone say something like this: . "It was an unexpected surprise when a pair of baby twins was born at 12 midnight.". What is a surprise if not unexpected? What are twins if not a pair? Who can be born but a baby? When is midnight if not at 12? The expressions we use are full of redundancy. Your friend could just as well have said: . 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. Denny Cherry. mrdenny@mrdenny.com. twitter.com/. mrdenny. About Me. Author or Coauthor of 4 books. 6+ SQL Mag articles. Dozens of other articles. Microsoft MVP since Oct 2008. Microsoft Certified Master. 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. Ofir Weisse. EECS 582 – W16. 1. About the paper. Published in 1988. Summarized existing technologies. EECS 582 – W16. 2. Motivation – What’s In the Box? . (That we call a computer). EECS 582 – W16. “Redundant Array of Inexpensive Disks”. CONTENTS. Storage devices.. Optical drives.. Floppy disk.. Hard disk.. Components of Hard disks.. RAID technology.. 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. Reads and writes are equally fast.. Arrays of these disks are used to provide highly reliable storage.. Increasingly popular as they are fast and do not contain moving parts.. Magnetic Disks.. . What is a magnetic disk and how it works. 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. media. PM Video 10:28. Selecting a Hard Drive. Some considerations when selecting a hard drive:. Drive capacity. Today’s hard drives range from 60 GB – 10 TB. Spindle speed (measured in RPM). Common spindle speeds are: 3600, 5400, 7200, 10,000, and 15,000 RPM.