...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 Great Pacific Garbage Patch College Writing August 10, 2009 Using our oceans as garbage dumps has had negative effects on both sea life and the environment. Imagine walking by the beach in Carlsbad, California and dropping the cap from your soda bottle; as you reach to pick it up, a wave comes and sweeps it from your grasp. Three years later that cap is part of a floating island of debris in the North Pacific Ocean, that some estimate to be twice the size of Texas. Humans are having a devastating impact on the earth’s oceans. Billions of tons of recyclables have found their way to the middle of the ocean. Many studies regarding the impact of plastics on the environment have been done, yet little has been done to understand what devastating effects this will have on our environment in the future. The Great Pacific Garbage Patch is one of the largest trash vortexes known to researchers. It is interesting to know that, currently, more than 60 billion tons of plastic are produced each year, and less than 5% of that is ever recycled. (Walsh) Plastic bags, bottles, toys, sun glasses and even shoes can be found floating in this giant mass of garbage. It is located in the remote waters between California and Hawaii, does not have distinct boundaries and varies in length and location throughout the year. This area moves seasonally between 23° and 37° N latitude. (NOS) Ocean currents grab the garbage and take it out to sea. It accumulates in different places where...
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...The biggest landfill on the earth: Great Pacific Garbage Patch Can you imagine the amount of trash approximately fourteen times bigger than whole Slovakia? No? Then it is about time to make you familiar with Great Pacific Garbage Patch. This large floating landfill is the biggest one in the world. According to Charles Moore, discoverer of Great Pacific Garbage Patch (in 1977), "The ocean is downhill from everything" (as cited in Blomberg, 2011). Considering the fact that high percentage of all trash is produced on the land, it is very surprising then the biggest junk yard is actually in the water and not on the land. Even though, recently many people and companies started to care more about amount of trash in oceans, there is a lack of information about Great Pacific Garbage Patch and related issues among large number of population. First of all, Great Pacific Garbage Patch consists of two parts, Western and Eastern Pacific Garbage Patch as mentioned in article written by Jacob Silverman (n.d.). Some sources refer to Eastern one as Great Pacific Garbage Patch and do not talk about the other one (Boudreau et al., n.d.), even though they do not deny the existence of Western Pacific Garbage Patch it can cause some misunderstanding with names. In this essay, there will be used distinction of Eastern and Western Pacific Garbage Patch as well as collective name Great Pacific Garbage Patch. Eastern one is situated between Hawaii and California, the Western...
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...The Great Pacific Garbage Patch This article is about the trash that ends up in the oceans and builds up into a giant garbage patch. When people throw their garbage on the ground it ends up in a small body of water and eventually travels into the ocean and gets stuck in this unbelievably large collection of trash. I think it is terrible when people litter because that litter ends up in the oceans and can hurt many animals. This problem is very serious and needs to be looked at as a bigger problem. Even though there are a lot of other problems going on in the world today, this is a big one that is affecting harmless animals all over. Plastic bags are mistaken for jellyfish, bottle caps are also, and are fed to baby birds. This is proven when birds die and left inside the body are tons of bottle caps and broken down plastic. I think this problem can be solved or at least made a little better. One possible solution is to ban plastic bags so people use the reusable ones. They could also make recycling a law. I am not sure how much can be done of what is already in the garbage patch, but we can try to keep it from getting worse. Because the water flows so far, there could always be places set up to pick up garbage that was missed earlier. This garbage patch is out of control and is only going to get worse, unless we decide to do something about it. It hurts animals, our water and will eventually hurt...
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...INDIAN INSTITUTE OF INFORMATION TECHNOLOGY DESIGN AND MANUFACTURING (IIITD&M) KANCHEEPURAM GARBAGE SORTER Submitted by R Subhashini IIITDM KANCHEEPURAM JAN-MAY 2011 1|Page INDEX Chapter no Contents Pg No Abstract 4 1 Mission statement 5 2 QFD 7 3 Existing products 9 4 Concept generation and selection 12 Phase 1 Segregating lighter and heavier material 13 Phase 2 Segregating sand from heavier materials 15 Phase 3 Crusher 16 Phase 4 Metal detector 14 Phase 5 Segregating plastics 20 Phase 6 Segregating glass 28 5 Pro e models 31 6 Specifications 33 7 Block diagrams 35 8 PLM 37 9 Conclusion 42 2|Page References 43 List of figures 1 Quality function deployment 8 2 Manual sorter 9 3 Garbage sorter in Malaysia 10 4 Separation of metal by eddy current technique 16 5 Identification of plastics based on wavelength 20 6 (a) Plastic identification by spectroscope 22 (b) Plastic identification by laser diode 22 7 Identification of plastics 24 8 Separation of glass 25 9 Block diagram of garbage sorter 31 3|Page Abstract In recent years, environmental issues have drawn more attention and a wide Variety of regulations and measures are being enforced all over the world. Waste disposal is one of the biggest concerns for...
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...gre5ryry Gun-related violence is most common in poor urban areas and in conjunction with gang violence, often involving juveniles or young adults.[1][2] Gun violence is not new in the United States, with the assassinations of President Abraham Lincoln in 1865, and of Presidents James Garfield, William McKinley, and John F. Kennedy. High profile gun violence incidents, such as the assassinations of Robert F. Kennedy, Martin Luther King, Jr., and, more recently, the Columbine High School massacre, the Beltway sniper attacks, the Virginia Tech massacre, and the 2011 Tucson shooting, have fueled debate over gun policies.[3] There were 52,447 deliberate and 23,237 accidental non-fatal gunshot injuries in the United States during 2000.[4] The majority of gun-related deaths in the United States are suicides,[5] with 17,352 (55.6%) of the total 31,224 firearm-related deaths in 2007 due to suicide, while 12,632 (40.5%) were homicide deaths.[6] Policies at the Federal, state, and local levels have attempted to address gun violence through a variety of methods, including restricting firearms purchasing by youths and other "at-risk" populations, setting waiting periods for firearm purchases, establishing gun "buy-back" programs, targeted law enforcement and policing strategies, stiff sentencing of gun law violators, education programs for parents and children, and community-outreach programs. Research has found some policies such as gun "buy-back" programs are ineffective, while Boston's...
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...Garbage can model Past questions 1, what is it about organizations that have meant that we have ended up with a garbage can theory of decision making? 2, under what organizational conditions would the garbage can theory of decision making apply? Watson, 2006 Within the micropolitics, numerous goals and purposes The outcomes of every political engagement will strengthen the strategic position of the organization and compromise the organization’s long-term survival. The official structure and culture of the org (the formal blue print or ‘organizational design’, calculations and actions of organizational actors) contributes to the negotiated order of the organization. According to the control system and a narrowing career ladder, we see a pattern of order in which things seem ‘very organised’ and ‘disorganised’ – anarchic even. Organized anarchy was used to capture the quality of organizational life The term usefully brings out the rather paradoxical quality of all organizational processes: their tendency, at the same time, to be both very organized and ‘very disorganized’. The garbage can model of organizational choice developed by these same researchers can usefully help us see how this ‘disorganized-organization’ quality of organized life manifests itself in decision making situations in organizations generally. Definition: garbage can model of organizational choice Organizational decisions are influenced by the various problems that exist at...
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...Evol. Inst. Econ. Rev. 4(1): 143–170 (2007) ARTICLE Econo-physics: A Perspective of Matching Two Sciences Yuri YEGOROV Institute for Advanced Studies, Stumpergasse 56, A-1060, Vienna, Austria, and University of Vienna, Department of Industry and Energy, Brünner Strasse, 72, A-1210, Vienna, Austria. E-mail: yegorov@ihs.ac.at Abstract The present article marks some potentially fruitful dimensions of economic research based on principles of economic theory but using more analogies with physics. Molecular structure of society with its different states, principles generating spontaneous order different from “invisible hand”, social analogies of the concepts of temperature and pressure in physics are investigated. Some analogies between phase transitions in physics and transition between different social regimes can reveal the areas of stability of liberal regimes as well as possibility of spontaneous emergence of different social orders. A possibility to expand neoclassical economics to capture Marxism and nationalism in a formal mathematical framework is also discussed. Keywords: economic structures, origin of order, econo-physics, socio-physics. 1. Introduction This article is methodological. It focuses on economic and social questions that are rarely touched by economic theorists despite their obvious importance for our understanding of economic processes in the world. No fully formalized model will be proposed here. Instead, the focus will be on interaction between...
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...(Speech delivered by Board Member Angelica Jones Alarva on Drug Awareness in the Province of Laguna in 2010) Magandang gabi po sa inyong lahat. Isa pong karangalan sa akin ang makasama kayo ngayong gabing ito. Naiintindihan ko po na sa pagtitipong ito ay may isang isyu tayong talakayin. Alam natin natin ang kahalagahan na masolusyunan ito at alam natin na may paraang maari nating gawin. Sino po dito sa inyo ang nakasubok nang mag-drugs? (Make some interactive discussion here. Let the crowd laugh and answer your question.) Madalas po natin marinig kapag ang isang tao ay hyper na hyper at aktibong aktibo ang tanong na: Nakadroga ka ba? O, ano na naman ang tinira mo? Sa mga barkadahan po, madalas natin ito maririnig. Sa panahon po ngayon ang salitang droga ay naging karaniwang salita na lamang. Ginagamit natin ang salitang droga o bawal na gamot na para bang ito’y ordinaryong isyu na lamang. Kunsabagay, tama po tayo sa isang banda. Ang usapin sa droga ay usaping napakatagal na nating pinaguusapan subalit hindi natin makita ang solusyon. Kung titingnan natin ang isyu, parang dead end. Darating ang halalan, may tatayo at magsasabi susugpuin ang droga, may mga organisasyong bubuuin para sugpuin ang droga, may mga seminars at symposium na gagawin para maging aware ang mga tao tungkol dito. Tama po ba yun? Maluluklok sa posisyon at malilimutan ang naipangako nang nagdaang halalan. Ngayon pong gabi, mayroon po akng isang layunin at sana ang mensaheng ito ay makatulong sa ating...
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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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...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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...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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...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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...A Garbage Can Model of Organizational Choice Organized anarchies are organizations characterized by problematic preferences, unclear technology, and fluid participation. These are organizations-or decision situations-characterized by three general properties. 1) Problematic preferences: In the organization it is difficult to impute a set of preferences to the decision situation that satisfies the standard consistency requirements for a theory of choice. The organization operates on the basis of a variety of inconsistent and ill-defined references. It discovers preferences through action more than it acts on the basis of preferences. 2) Unclear Technology: Although the organization manages to survive and even produce, its own processes are not understood by its members. It operates on the basis of simple trial-and-error procedures, the residue of learning from the accidents of past experience, and pragmatic inventions of necessity. 3) Fluid Participation: Participants vary in the amount of time and effort they devote to different domains; involvement varies from one time to another. As a result, the boundaries of the organization are uncertain and changing; the audiences and decision makers for any particular kind of choice change capriciously. They are particularly conspicuous in public, educational, and illegitimate organizations. To build on current behavioural theories of organizations in order to accommodate the concept of organized anarchy, two major...
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