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Virtual memory

In computing, virtual memory is a memory management technique that provides an "idealized abstraction of the storage resources that are available on a given machine" which "creates the illusion to users of a large memory". The computer's operating system, using a combination of hardware and software, maps memory addresses used by a program, called virtual addresses, into physical addresses in computer memory. Main storage, as seen by a process or task, appears as a contiguous address space or collection of contiguous segments; the operating system manages virtual address spaces and the assignment of real memory to virtual memory. Address translation hardware in the CPU referred to as a memory management unit, automatically translates virtual addresses to physical addresses. Software within the operating system may extend these capabilities to provide a virtual address space that can exceed the capacity of real memory and thus reference more memory than is physically present in the computer.

The primary benefits of virtual memory include freeing applications from having to manage a shared memory space, increased security due to memory isolation, being able to conceptually use more memory than might be physically available, using the technique of paging. Virtual memory makes application programming easier by hiding fragmentation of physical memory. Memory virtualization can be considered a generalization of the concept of virtual memory. Virtual memory is an integral part of a modern computer architecture. While not necessary and virtual machines can employ hardware support to increase performance of their virtual memory implementations. Older operating systems, such as those for the mainframes of the 1960s, those for personal computers of the early to mid-1980s have no virtual memory functionality, though notable exceptions for mainframes of the 1960s include: the Atlas Supervisor for the Atlas THE multiprogramming system for the Electrologica X8 MCP for the Burroughs B5000 MTS, TSS/360 and CP/CMS for the IBM System/360 Model 67 Multics for the GE 645 The Time Sharing Operating System for the RCA Spectra 70/46and the operating system for the Apple Lisa is an example of a personal computer operating system of the 1980s that features virtual memory.

During the 1960s and early 70s, computer memory was expensive. The introduction of virtual memory provided an ability for software systems with large memory demands to run on computers with less real memory; the savings from this provided a strong incentive to switch to virtual memory for all systems. The additional capability of providing virtual address spaces added another level of security and reliability, thus making virtual memory more attractive to the market place. Most modern operating systems that support virtual memory run each process in its own dedicated address space; each program thus appears to have sole access to the virtual memory. However, some older operating systems and modern ones are single address space operating systems that run all processes in a single address space composed of virtualized memory. Embedded systems and other special-purpose computer systems that require fast and/or consistent response times may opt not to use virtual memory due to decreased determinism.

The hardware to translate virtual addresses to physical addresses requires significant chip area to implement, not all chips used in embedded systems include that hardware, another reason some of those systems don't use virtual memory. In the 1940s and 1950s, all larger programs had to contain logic for managing primary and secondary storage, such as overlaying. Virtual memory was therefore introduced not only to extend primary memory, but to make such an extension as easy as possible for programmers to use. To allow for multiprogramming and multitasking, many early systems divided memory between multiple programs without virtual memory, such as early models of the PDP-10 via registers. A claim that the concept of virtual memory was first developed by German physicist Fritz-Rudolf Güntsch at the Technische Universität Berlin in 1956 in his doctoral thesis, Logical Design of a Digital Computer with Multiple Asynchronous Rotating Drums and Automatic High Speed Memory Operation does not stand up to careful scrutiny.

The computer proposed by Güntsch had an address space of 105 words which mapped on to the 105 words of the drums, i.e. the addresses were real addresses and there was no form of indirect mapping, a key feature of virtual memory. What Güntsch did invent was a form of cache memory, since his high-speed memory was intended to contain a copy of some blocks of code or data taken from the drums. Indeed he wrote: “The programmer need not respect the existence of the primary memory, for there is only one sort of addresses by which one can program as if there were only one storage.” This is the situation in computers with cache memory, one of the earliest co

Jacob Hoornbeck Stone House

The Jacob Hoornbeck Stone House is located at the junction of Boice Mill and Drum Farm roads in Kerhonkson, New York, United States, a hamlet of the Town of Rochester in Ulster County. It was erected in the early 19th century using the Georgian architectural style, incorporating an earlier house as its rear wing, it reflects a generation of stone houses built by the descendants of Dutch settlers in the town, features like the full stone gable fields on either end. In 1999 it was listed on the National Register of Historic Places as part of a multiple property submission of stone houses in Rochester; the house is located at the northwest corner of the junction of the two roads. It is on a 15-acre lot that straddles Boice Mill Road to Mill Brook south of the property, where the remains of a mill once on the site can be seen at the base of a steep waterfall. To the east, across Drum Farm Road, are barns built when the house was the center of a much larger dairy farm; the surrounding neighborhood is a rural area of woodlots.

The building itself is a two-and-a-half-story five-bay stone structure topped with a gabled roof shingled in asphalt with two interior brick chimneys at either end. A one-and-a-half-story rear wing, the original house on the site, projects to the north at the east corner, it has a gabled roof shingled in asphalt with a modern porch over its eastern entrance. At the northwest corner a hip roofed porch connects the two sections. At the center of the south facade of the main block is the recessed main entrance, a paneled door set between paneled pilasters with capitals that divide the sidelights, they support an entablature with a full-width divided transom. There are two small two-over-two sash windows on either side. All other windows are 12-over-12 with louvered wooden shutters; the paneled front door opens into a modified central hall divided into front and rear sections separated by an arched entryway. The hallway divides two rooms of equal size on either side; this arrangement is replicated on the second floor.

The rear wing has a kitchen on a loft upstairs. Throughout the building, all finishes are original. Records show the water rights to the property in the hands of Jacob Hoornbeck's family from 1703 onward, they established a mill on the brook near the remains of which can still be seen. It is not known; the Georgian main block was added to it around the turn of the 19th century. In that century the kitchen wing may have been used as a hoop shop. A few changes were made to the house during that period. A front porch was removed the property's listing on the Register. There have been no other significant alterations to the house in the course of its existence. National Register of Historic Places listings in Ulster County, New York

Arthur Mills (Indian Army officer)

Major-General Sir Arthur Mordaunt Mills, was a senior officer in the British Indian Army. Arthur Mordaunt Mills was born on 13 August 1879, the son of Colonel Arthur McLeod Mills, an officer in the Indian Army, his wife Elizabeth Louisa Jane née Pughe. In 1908, he married Winifred Alice, daughter of Colonel R. H. Carew,; the eldest son Arthur William, married Rosemary Anne, only daughter of Major Edmond Meacher of Enton Leys in Whitley. The daughter, Patricia Elizabeth, married the diplomat Sir Hugh Southern Stephenson, son of Sir Hugh Stephenson, who had served as Governor of Burma. In 1940, Mills married, Hilda Grace Shirley, younger daughter of Harry Gavin Young, an officer in the Madras Police. Following schooling at Wellington College, Mills was commissioned into the Devonshire Regiment as a 2nd Lieutenant on 4 May 1901, he was commissioned into the Indian Army with the same rank on 10 October 1902, promoted to Lieutenant the following August and became a Captain on 29 March 1910. He was posted as Adjutant and Quarter Master at the Staff College in Quetta between April 1913 and September 1914.

During World War I, Mills was a Staff Captain in France between June and November 1915, after which he served as a temporary Major with the 14th Battalion of the Gloucestershire Regiment until 28 March 1916. The following day, he was promoted to the full rank of Major. Between 2 April 1916 and 5 July 1917, he was a temporary Lieutenant-Colonel in the 17th Battalion of the Lancashire Fusiliers. Over the course of the conflict, he was wounded, mentioned in despatches three times and received the Distinguished Service Order with two bars. Mills was promoted to the rank of Brevet Lieutenant-Colonel on 3 June 1919. An appointment as an Instructor at the Senior Officers' School in Woking was followed by a posting as an Assistant Adjutant General in India between July 1929 and July 1930. Mills was appointed Brigadier Commander on 4 July 1930, he served as an Aide-de-Camp to the King between March 1933 to May 1935 and became Military Advisor in Chief to the Indian State Forces on 16 March 1935. He retired in 1939, but remained Colonel of the 4th Prince of Wales's Own Gurkha Rifles until 1950, having held the post since 1935.

Mills was appointed a Companion of the Order of the Bath in 1932 and a Knight Bachelor in 1938. He died on 8 October 1964. Sir Arthur Mordaunt Mills by Bassano Ltd, 1 June 1961. Half-plate film negative. National Portrait Gallery, London

Virginia Jetzt!

Virginia Jetzt! was a German Indie-Pop band founded in the small town of Elsterwerda in Brandenburg in 1999. The band has released four albums so far, their 2003 debut album Wer hat Angst vor Virginia Jetzt? — a reference to the Edward Albee play Who's Afraid of Virginia Woolf? — followed by Anfänger in 2004, Land Unter in 2007, "Blühende Landschaften" in 2009. Anfänger spawned three single releases. In 2005, the band represented Brandenburg in the Bundesvision Song Contest 2005, with the song "Wahre Liebe", placing 8th with 54 points. January 2007 saw the band release their album Land Unter, containing the singles "Bitte bleib nicht, wenn du gehst" and "Mehr als das". Virginia jetzt! Pophymnen Wer hat Angst vor Virginia Jetzt! Anfänger Anfänger Tour Edition Land Unter Blühende Landschaften Official Website

The Grid (American TV series)

The Grid, hosted by podcasting and public radio host Jesse Thorn, is an American fifteen-minute weekly rundown of what is trending in indie culture. Each week on IFC, The Grid recommends movies, music and gadgets of interest. Joining Jesse are an array of up-and-coming comedians, offering their own opinions on what is trending now; the Grid aired every Thursday at 7:45 p.m. EST, 4:45 PST on IFC. Various segments from the week's episode can be viewed online at IFC.com and on social networking websites. The Grid premiered on IFC on September 9, 2010 The program's executive producer is Michael B. Pressman, the producer is Michelle Von Wald; each episode is written by Joshua Weiner. Although Jesse Thorn is the only correspondent to appear on every episode, he did not become the host until episode 104; the first two episodes were hosted by Alex Berg, the third was hosted by correspondent Sarah Lane. Other correspondents included Alonso Duralde, Whitney Pastorek, Kat Lyn, Ryan Downey, Taylor Orci and Shira Lazar.

The director of these episodes was Lew Abramson. Beginning with episode 111, Michael B. Pressman took over as the show's director and the show's regular correspondents became those listed below. Jesse Thorn runs MaximumFun.org, home of the nationally syndicated The Sound Of Young America radio show and podcast. As part of his show, Jesse interviews musician, or filmmaker each week, his previous guests have included Judd Apatow and Fred Armisen. Jesse co-hosts the podcast Jordan, Jesse, Go! With long-time sidekick and fellow Grid contributor Jordan Morris. In addition to his radio shows, Jesse hosts the video podcast Put This On, a guide to dressing like a grownup in the world of men's fashion. Marisa Pinson, is co-author of Dealbreaker: The Definitive List of Dating Offenses, is an active member of the Upright Citizens Brigade Theatre in Los Angeles. Jordan Morris, is The Grid’s resident man on the street attending everything from Food Truck Battles to Anime Burlesque Shows. Kulap Vilaysack has appeared on NBC’s The Office, covers comic books, kitschy DVD releases and exciting new gadgets.

Vince Mancini, editor in chief of popular movie blog FilmDrunk.com, covers film releases. Executive Producer: Michael B. Pressman Producer: Michelle Von Wald Supervising Producer: Curtis Gwinn Staff Writers: Joshua Weiner, Alex Berg Editors: Carlos Pena, Joey Rabier, Brady Hammes, Matt Silfen, Jason Haberman, Cameron Gibson. Sound: Aaron D. Murphy, Ilana Urbach, Thomas Curley Production Manager: Rachel Garza Director of Photography: Jared Varava, Andrew Bridgewater, Dave Chung Make-Up: Michal Braun, Natalia Senina Stylist: Lauren Shapiro, Amber Sellers Production Assistants: Zachary Bradshaw, Cameron Gibson Executive Producer for IFC: Douglas Marshall Director, Production for IFC: Sara Morrow Production Supervisor for IFC: Keisha Punter Operations Manager for IFC: Ted Leuci Executive Producers: Debbie DeMontreux, Jennifer Caserta, Christine Lubrano The Grid on IMDb

Jesse James (politician)

Jesse William James was an American politician from Texas. A member of the Democratic Party, James served as Texas State Treasurer from 1941 until his death in 1977, his near 36-year tenure made him the longest serving Texas State Treasurer. James served in the Texas House of Representatives from 1933 to 1937, when he resigned to accept a position in the office of the state treasurer; when the incumbent state treasurer, Charley Lockhart, resigned due to poor health, Governor Coke R. Stevenson appointed James to the office. James continued to be reelected as state treasurer, he was succeeded by Warren G. Harding, whom James had defeated for reelection in 1956. James was born on October 10, 1904, in Sand Grove, south of Milano, Texas, in Milam County, to John A. and Delia James. Jesse was one of 11 children, his father was called "Jesse James" by his associates. James was raised in Texas, his father died when he was young, Jesse assisted his mother in raising his ten siblings. He graduated college with a degree in business administration and graduated from Jefferson Law School.

He became a merchant in his home county. In 1932, James was nominated by the Democratic Party for the Texas House of Representatives seat for District 65, representing parts of Milam and Lee counties, he won the election, was sworn into the House in 1933. He was reelected twice. In 1937, Charley Lockhart, the Texas State Treasurer, appointed James as the first assistant chief clerk. James resigned from the Texas House to take the role on September 1. In October 1941, Lockhart resigned from office due to poor health. Coke R. Stevenson, the Governor of Texas, appointed James to succeed him on October 25. 1941. In James' first election as Texas State Treasurer in 1942, he finished in second place out of five candidates in the primary election, but emerged victorious in the runoff election. In 1950, he was selected as the first vice president of the National Association of State Auditors and Treasurers. In his career, he was criticized for keeping the state's funds in checking accounts rather than savings accounts, with one political challenger claiming that this cost the state an estimated $91 million in interest.

James faced few strong challenges for reelection after his initial election in 1942 running unopposed in the general election as no Republican Party candidate would file to run against him. He was challenged by Warren G. Harding the county treasurer for Dallas County in the Democratic primary in 1956, who James defeated. James drew Democratic and Republican challengers in 1974, receiving only 54% of the vote in the Democratic primary that year due to the strong challenge from Don Yarbrough. In total, James was re-elected a Texas state record. James married Mary Zana Belle, from Mansfield and worked as a teacher in Thorndale, they lived in Milam County, had a daughter named Doris and two grandchildren. James sold boats and developed the Lake Travis Lodges. In life, James developed health complications, he had diabetes, causing poor blood circulation and had two amputations performed on his left leg: around the calf muscle in December 1976 and above the knee in January 1977. He was hospitalized at Seton Medical Center in Austin, Texas, on September 19.

He suffered a fatal heart attack on September 29, was buried in the Texas State Cemetery in Austin. Jesse James at Find a Grave