...Distributed Garbage Collection A study and comparison of Mark-Sweep and Reference Counting Tanmay Mogra Y7471 Shashwat Mishra Y7416 Table of Contents History and Motivation 1 ------------------------------------------------ Work Completed Mark and Sweep ------------------------------------------------2 Basic Algorithm ------------------------------------------------2 Strengths and Weaknesses ------------------------------------------------2 Varations of Mark and Sweep -------------------------------------------------2 Reference Counting Basic Algorithm Strengths and Weaknesses 3 3 Mark and Sweep vs. Reference Counting Design/Implementation A Simulation of Reference Counting using JAVA's ----------------------------------------------Remote Method Invocation API Conclusion References -----------------------------------------------------------------------------------------------6 7 5 -----------------------------------------------4 Variations of Ref. Counting --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------3 3 History and Motivation The problem statement requires one to study and compare the efficiency of two garbage collection algorithms, Mark and Sweep and Reference Counting, in the context of distributed object systems. It also involves the implementation of one of the two algorithms. Modern systems come with limited memory...
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...the real (memory) cost of what you create. Therefore always measure. It's also very important to test on devices because the emulator or simulator will not provide an accurate representation of a device this article will delve into some of the best practices for effectively using memory and provide tips to help achieve high performance. IOS and OS X users can use Apple Instruments to get accurate memory measurements of their applications, whereas Android users have the Android Device Manager at their disposal. Managed languages make use of garbage collection to reclaim memory that is allocated to objects that are no longer in use. There are two garbage collectors available with Xamarin.iOS (Xamarin.Android only has SGen): •Boehm – This is a non-generational garbage collector. It is the default garbage collector used in Xamarin.iOS. When garbage collection occurs, the entire heap will be collected. •SGen – This is a generational garbage collector and should be preferred over Boehm. This is because SGen, compared to Boehm, performs...
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...the real (memory) cost of what you create. Therefore always measure. It's also very important to test on devices because the emulator or simulator will not provide an accurate representation of a device this article will delve into some of the best practices for effectively using memory and provide tips to help achieve high performance. IOS and OS X users can use Apple Instruments to get accurate memory measurements of their applications, whereas Android users have the Android Device Manager at their disposal. Managed languages make use of garbage collection to reclaim memory that is allocated to objects that are no longer in use. There are two garbage collectors available with Xamarin.iOS (Xamarin.Android only has SGen): •Boehm – This is a non-generational garbage collector. It is the default garbage collector used in Xamarin.iOS. When garbage collection occurs, the entire heap will be collected. •SGen – This is a generational garbage collector and should be preferred over Boehm. This is because SGen, compared to Boehm, performs...
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...Memory Management in Mac OS Memory Management in Mac OS Mindfire Solutions www.mindfiresolutions.com March 6, 2002 Abstract: This paper discusses memory management by macintosh operating system. This paper is a summarized form of “Inside Macintosh: Memory” and is directed towards developers who are new to Mac development but had previous development experience on other operating system. After going through this article you will be familiar with memory architecture in Mac, ways to allocate and deallocate memory, using temporary memory, A5 world, heap management, heap zones, heap fragmentation and several other features provided by memory manager. MEMORY MANAGEMENT IN MAC OS.................................................................. 1 ORGANIZATION OF MEMORY IN MAC OS ......................................................... 3 The System Heap ..................................................................................................... 4 The System Global Variables................................................................................... 4 ORGANIZATION OF MEMORY IN AN APPLICATION PARTITION 1...................................... 4 The Application Stack 1........................................................................................... 6 The Application Heap 1........................................................................................... 6 The Application Global Variables and A5 World 1 .................................................
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...Abstract—This paper addresses the topic of methods for producing inter procedural static data flow graphs. The method used in this paper is a sort of progressive mining approach: A start location for the data flow edges is outlined, and through multiple iterations, the forward data flow step operation is taken on the universe, until no new paths have been found. I. INTRODUCTION New tools often provide novel approaches to longstanding problems. In the next update of C-Atlas, Ensoft intends to update the capabilities of C-Atlas. These improvements are intended to provide a customizable approach to evaluating a program’s design, structure, and security. Such an update seeks to address any number of problems. Analyzing a C program’s memory management is one such problem. This project would seek to use C-Atlas to better analyze C memory management. In memory leak (memory management) analysis, the user must show that for every path forward from an variable’s allocation, there exists at least one deallocation site for that variable. This task is trivial, unless the variable’s allocation and deallocation(s) are separated by a vast field of possible control flow. C-Atlas offers a flexible interface for data flow graph generation as a solution to this problem. Through this interface, one may then produce connected data flow graphs, allowing a single variable’s path to be traced through multiple functions. This visual aide can greatly increase the time efficiency of performing memory...
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...P ra c t i c a l ve ri f i c a t i o n & s a fe g u a rd tools for C/C++ F Michaud . R. Carbone DRDC Valcartier Defence R&D Canada – Valcartier Technical Report DRDC Valcartier TR 2006-735 November 2007 Practical verification & safeguard tools for C/C++ F. Michaud R. Carbone DRDC Valcartier DRDC Valcartier Technical Report DRDC Valcartier TR 2006-735 November 2007 Principal Author Approved by Yves van Chestein Head/IKM Approved for release by Christian Carrier Chief Scientist c Her Majesty the Queen in Right of Canada as represented by the Minister of National Defence, 2007 c Sa Majest´ la Reine (en droit du Canada), telle que repr´sent´e par le ministre de la e e e D´fense nationale, 2007 e Abstract This document is the final report of an activity that took place in 2005-2006. The goal of this project was first to identify common software defects related to the use of the C and C++ programming languages. Errors and vulnerabilities created by these defects were also investigated, so that meaningful test cases could be created for the evaluation of best-ofbreed automatic verification tools. Finally, when relevant, best practices were inferred from our experiments with these tools. ´ ´ Resume Ce document est le rapport final d’un projet de recherche qui a eu lieu en 2005-2006. Le but de ce projet ´tait avant tout d’identifier les d´fauts logiciels courants li´s ` l’utilisation des e e e a langages de programmation C et C++. Les erreurs et vuln´rabilit´s...
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...Cst 1215 OS_HW_Ch. 2_2015.02.07 1. Explain the fundamental differences between internal fragmentation and external fragmentation. For each of the four memory management systems explained in this chapter (single user, fixed, dynamic, and relocatable dynamic), identify which one causes each type of fragmentation. 1A. Internal fragmentation is the area occupied by a process but cannot be used by the process. This space is unusable by the system until the process release the space. External fragmentation exists when total free memory is enough for the new process but it's not contiguous and can't satisfy the request. Storage is fragmented into small holes. 1B. Single-User Contiguous Scheme: Program is loaded in its entirety into memory and allocated as much contiguous space in memory as it needs. Jobs processed sequentially in single-user systems Requires minimal work by the Memory Manager Register to store the base address Accumulator to keep track of the program size Disadvantages of Single-User Contiguous Scheme: Doesn’t support multiprogramming not cost effective Fixed Partitions: Main memory is partitioned; one partition/job. Allows multiprogramming Partition sizes remain static unless and until computer system id shutdown, reconfigured, and restarted requires protection of the job’s memory space requires matching job size with partition size Disadvantages: Requires entire program to be stored contiguously Jobs are allocated space on the basis of first available...
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...Comparison between Oracle 12c and Microsoft SQL Server 2012 Students Name Institutional Affiliation Contents Introduction 3 History. 3 Processes 3 Transaction control. 3 Downtime processes. 4 Data guard and AlwaysOn comparison. 5 Memory 6 Network 8 Application 9 Conclusion 11 References. 12 Introduction In the modern world, businesses depend largely on databases and therefore in a case whereby such databases became unavailable then it would be an indication the businesses will also fail. As a result, there are lots of different databases in the market with different characteristics in term of memory planning, processes, and physical appearance. It is the obligation of an organization to understand the features of such databases to make the correct choice regarding which one to purchase. Therefore, an outline of the comparisons between the Oracle 12c and the Microsoft SQL Server 2012 has been given. History. The Microsoft SQl Server was initially released in the year 1989, and major improvements have been done o it since then. On the hand, the Oracle database was released in the year 1980. Both databases use the c++ language to carry out their operations which in turn makes them compatible with a lot of computing devices. However, Oracle uses C language as well. Microsoft SQL is widely used in Windows operating systems while on the other hand, Oracle is used in...
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...DMB/380 February 10th 2014 DMB/380 February 10th 2014 Art Museum Database By: For the past couple of years, a local art Museum has been collecting different art pieces from various artists. The Museum then displays the art throughout different galleries across town. The collection has significantly grown and it is now complicated for the museum to keep track of the many different artist and their different art pieces and collections, as well as where the art is located, whether it is stored in different galleries or the Museum itself. It is important for the Museum to develop a database that can keep track of the different art pieces, the artists, the different locations the pieces can be located and a total amount of pieces collected since it continues to grow at a very fast rate. The database will help the Museum substantially as well as the artists who create many various art pieces. Problems and Constraints The Museum continues to grow and it has become difficult for the manager and staff to keep track of the art collection. Not having a database that can tie the artist with his art and the location of it has caused the Museum to lose some of the different art pieces which in return equal financial losses to the Museum. Another problem the Museum continues to have is keeping track of when and where the art is being displayed. Most of the art is displayed for a period of time throughout the different galleries then either stored back...
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...The MMA is one of the most public in the country, and more heavily dependent on the mem- bership contribution than any other [museum]. Like most, it is underendowed and underfunded from reliable public funds. In fact, the American Association of Museums reports that only about 60 percent of America’s 2000-plus art museums have enough income from their endowment to cover their operating costs. Nevertheless, this institu- tion has chosen to be public, with free access, and this is very noble. It is wonderful that the museum has decided not to belong to an agglomeration of very rich people. This museum has more character than it thinks it has. It has the best balanced collection between Western and non-Western art of any museum in the country. We have not chosen to sell or promote the unique aspects of this collection or the museum’s emphasis on historical context.What we have are the makings of an institu- tion that is very different from other museums, and we ought to be able to make that into an advantage rather than apologize for...
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...Will Hawkins is the Museum Coordinator at the Tuscaloosa Museum of Art, home of The Westervelt Collection. Mr. Hawkins graduated from Huntington College in Montgomery, AL with a degree in History. After college, he began working in the restaurant industry and continued for 15 years. While working in Tuscaloosa, he began volunteering with the Tuscaloosa Museum of Art, and shortly after, he was hired as a member of the staff and worked his way up to becoming the Museum Coordinator. The Tuscaloosa Museum of Art houses The Westervelt Collection comprised of approximately 1000 works of fine and decorative arts. The collection was amassed by Jack Warner as investments for Gulf States Paper, now the Westervelt Company. Operating under a nonprofit foundation, the museum was asked by the Westervelt Company to share its collection with the community. Being a collection that was pieced together simply by the tastes of one man, the Westervelt Collection is remarkably cohesive. Hawkins stated that's he is always amazed at the story told through the pieces of art. There are four paid staff members at the museum. Mr. Hawkins and Kathy Thurman are the only two professional staff members. The museum employs two part-time college students. Mr. Hawkins’s duties as Museum Coordinator include a very wide range of daily tasks. From handling the art to training docents and from scheduling tours to giving them himself, Hawkins’s day is packed with many different tasks. The museum has gone through...
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...Olowe of Ise “It is insufficiently understood that a museums power lies not in the possession of objects and collections, but in the acceptance of its authority to name them by both label and context. This is the most jealously guarded divine right of the museum as the curator of soi-disant public collections” – Duncan F. Cameron. Duncan F. Cameron served as a museum curator and director in the Brooklyn Museum in the New York City Borough of Brooklyn, the second largest museum in New York City and one of the largest in the United States. Duncan served in the museum from 1971-1974. An artist once told me, “Art is in the eyes of the beholder” – anonymous. It’s a statement with a broad perspective of thought and meditation. First I would like to give an example of what the quote by Duncan meant can be seen by the work of Constantine Petridis, a museum curator of African art gallery in the Cleveland Museum of art. He explains objects from the same culture are displayed together and differentiated with those of their neighbors. This concept shows the formal and stylistic relationships between neighboring and familiar artistic customs or traditions that ex-plains the distinctiveness of the arts of distinct people. An addition to the regional framework, thematic connections are highlighted through the use of gallery cards which explain topics of artists, leadership, masks and masquerades, styles and the supernatural. Gallery cards provide photo, descriptions and narrative text linking...
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...Gokhale Cross Road- Pune-400016 Phone: 9975418176 Fax: N.A Email:11030141031@sicsr.ac.in Web Address:N/A Business Description: Let’s Recycle enterprises will operate in Pune and suburbs, in cooperation with the local corporation, to pick-up and purchase the segregated garbage from individuals. The collected waste will be recycled for the production of best quality organic compost fertilizer and additional bi-products like charcoal, tar, plastic and glass bottles. This business will be recession proof because the garbage will be coming out in any case. Let’s recycle will also set its foot in nutritious organic farming and mushrooms cultivation. Our unique features of the business will be1) It will be a helping hand to the municipal corporation for collection of the waste and keeping the city clean and green. Our Business will also help the city to reduce the pollution of the city and hence reduce the carbon credits. The filthy scene in and around the city will be reduced. 2) The citizens will be paid for their daily contribution of the segregated garbage which will reduce the possibility of people throwing garbage anywhere. 3) Web portal which will help the customer to send request for collection of the garbage, registering them with Let’s Recycle and to check their contribution and payment information. If we see...
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...My ideal house My ideal house would cost a great many thousands of dollars and therefore, even if I am very successful in life, I do not suppose that I shall possess it for a very long time. However there is no harm in dreaming, especially if the dream provides the driving force to turn fantasy into fact. As I live in Singapore, i would like my ideal house to be situated either on one of the residential estates, right outside the bustle of the city center, or on one of the coast roads so that the cool breezes from the ever beautiful China sea could waft through my windows. Wherever my house was, it would stand in it sown grounds so that I would not, on any side, be over-looked by neighbors. The gardens, with which it would be surrounded would be very beautiful, full of colorful tropical flowers; orchids and canna lilies and with many glowing flowering shrubs such as bougainvillaea and frangipani. There would be tall leafy trees for shade and underneath them, my private swimming bath would be built, where we could relax and swim in the heat of the day. there would be pleasant paths winding through the green grass and comfortable seats where my family and I could rest, when the day's toil was over. The house itself would be built of white stone which is both cool and weather-proof. It would be on two storeys, because I like the habit of sleeping upstairs. It would embody features from both the Eastern and Western worlds. In front of it, I would have a large path with...
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...the problem of solid waste management at College of Education, Ikere – Ekiti located in South West Nigeria as an institution. Since solid waste is being generated in the school, it is imperative to make sure they are properly handled in the specified way. Solid waste management is defined as the branch of Solid Waste Engineering associated with waste control of generation, storage, collection and transfer, transportation, processing and disposal of solid waste in a manner that is in accordance with the best principle of Public Health Economics, Engineering Conservation, aesthetics and other environmental consideration. The various problems facing the management of these solid wastes in the College were discussed and appropriate solutions were suggested. INTRODUCTION Waste according to Fantola (1997) can be defined as any material flow pattern that is rejected by the society. Waste according to their state can be either solid or liquid. This paper seems to concentrate on the management of solid waste alone. Also, The Resource Conservation and Recovery Act define solid wastes as: "Any garbage, refuse, sludge from a waste treatment plant, water supply treatment plant, or air pollution control facility and other discarded material including solid, liquid, semisolid, or contained gaseous material resulting from industrial, commercial, mining, and agricultural operations and from community...
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