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Observer Effect (information Technology)
In information technology, the observer effect is the impact on the behaviour of a computer process caused by the act of observing the process while it is running. For example: if a process uses a log file to record its progress, the process could slow down. Furthermore, the act of viewing the file while the process is running could cause an I/O error in the process, which could, in turn, cause it to stop. Another example would be observing the performance of a CPU by running both the observed and observing programs on the same CPU, which will lead to inaccurate results because the observer program itself affects the CPU performance (modern, heavily cached and pipelined CPUs are particularly affected by this kind of observation). The observer effect could either have a positive or negative impact on the computer process behaviour. A positive impact can be software bugs, also known as Heisenbugs, which diminish or change their negative behavior when observation mechanisms, such ...
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Information Technology
Information technology (IT) is a set of related fields within information and communications technology (ICT), that encompass computer systems, software, programming languages, data processing, data and information processing, and storage. Information technology is an application of computer science and computer engineering. The term is commonly used as a synonym for computers and computer networks, but it also encompasses other information distribution technologies such as television and telephones. Several products or services within an economy are associated with information technology, including computer hardware, software, electronics, semiconductors, internet, Telecommunications equipment, telecom equipment, and e-commerce.. An information technology system (IT system) is generally an information system, a communications system, or, more specifically speaking, a Computer, computer system — including all Computer hardware, hardware, software, and peripheral equipment � ...
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Software Bug
A software bug is a design defect ( bug) in computer software. A computer program with many or serious bugs may be described as ''buggy''. The effects of a software bug range from minor (such as a misspelled word in the user interface) to severe (such as frequent crashing). In 2002, a study commissioned by the US Department of Commerce's National Institute of Standards and Technology concluded that "software bugs, or errors, are so prevalent and so detrimental that they cost the US economy an estimated $59 billion annually, or about 0.6 percent of the gross domestic product". Since the 1950s, some computer systems have been designed to detect or auto-correct various software errors during operations. History Terminology ''Mistake metamorphism'' (from Greek ''meta'' = "change", ''morph'' = "form") refers to the evolution of a defect in the final stage of software deployment. Transformation of a ''mistake'' committed by an analyst in the early stages of the softw ...
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Heisenbug
In computer programming jargon, a heisenbug is a software bug that seems to disappear or alter its behavior when one attempts to study it. The term is a pun on the name of Werner Heisenberg, the physicist who first asserted the observer effect of quantum mechanics, which states that the act of observing a system inevitably alters its state. In electronics, the traditional term is probe effect, where attaching a test probe to a device changes its behavior. Similar terms, such as ''bohrbug'', ''mandelbug'', ''hindenbug'', and ''schrödinbug'' (see the section on related terms) have been occasionally proposed for other kinds of unusual software bugs, sometimes in jest. Examples Heisenbugs occur because common attempts to debug a program, such as inserting output statements or running it with a debugger, usually have the side-effect of altering the behavior of the program in subtle ways, such as changing the memory addresses of variables and the timing of its execution. O ...
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Debugging
In engineering, debugging is the process of finding the Root cause analysis, root cause, workarounds, and possible fixes for bug (engineering), bugs. For software, debugging tactics can involve interactive debugging, control flow analysis, Logfile, log file analysis, monitoring at the application monitoring, application or system monitoring, system level, memory dumps, and profiling (computer programming), profiling. Many Programming language, programming languages and Programming tool, software development tools also offer programs to aid in debugging, known as debuggers. Etymology The term ''bug'', in the sense of defect, dates back at least to 1878 when Thomas Edison wrote "little faults and difficulties" in his inventions as "Bugs". A popular story from the 1940s is from Admiral Grace Hopper. While she was working on a Harvard Mark II, Mark II computer at Harvard University, her associates discovered a moth stuck in a relay that impeded operation and wrote in a log book ...
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