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Server Hog
{{citations needed, date=November 2013 Server (or resource) hogging is where a user, program or system places excessive load on a server. "Hogging" aims to significantly degrade performance experienced for clients so that the server & resources itself are so heavily loaded that it fails to perform routine functions. History In the early years of time-sharing computer systems in the 1960s it was common for a single institutional mainframe to control many interactive terminals. In such an environment server lag is acutely perceived. Furthermore, in many operating environments, scarce server resources such as CPU-seconds were often metered and charged against the account of the user running the program. An unintentional server hog could prove extremely costly in financial terms. These programs were often called run-away programs or endless loops. Resource contention Server performance has many dimensions. Any subsystem that becomes excessively loaded can compromise the perfor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Server (computing)
A server is a computer that provides information to other computers called " clients" on a computer network. This architecture is called the client–server model. Servers can provide various functionalities, often called "services", such as sharing data or resources among multiple clients or performing computations for a client. A single server can serve multiple clients, and a single client can use multiple servers. A client process may run on the same device or may connect over a network to a server on a different device. Typical servers are database servers, file servers, mail servers, print servers, web servers, game servers, and application servers. Client–server systems are usually most frequently implemented by (and often identified with) the request–response model: a client sends a request to the server, which performs some action and sends a response back to the client, typically with a result or acknowledgment. Designating a computer as "server-class hardwa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet
The Internet (or internet) is the Global network, global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a internetworking, network of networks that consists of Private network, private, public, academic, business, and government networks of local to global scope, linked by a broad array of electronic, Wireless network, wireless, and optical networking technologies. The Internet carries a vast range of information resources and services, such as the interlinked hypertext documents and Web application, applications of the World Wide Web (WWW), email, electronic mail, internet telephony, streaming media and file sharing. The origins of the Internet date back to research that enabled the time-sharing of computer resources, the development of packet switching in the 1960s and the design of computer networks for data communication. The set of rules (communication protocols) to enable i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Bot
An Internet bot, web robot, robot, or simply bot, is a software application that runs automated tasks ( scripts) on the Internet, usually with the intent to imitate human activity, such as messaging, on a large scale. An Internet bot plays the client role in a client–server model whereas the server role is usually played by web servers. Internet bots are able to perform simple and repetitive tasks much faster than a person could ever do. The most extensive use of bots is for web crawling, in which an automated script fetches, analyzes and files information from web servers. More than half of all web traffic is generated by bots. Efforts by web servers to restrict bots vary. Some servers have a robots.txt file that contains the rules governing bot behavior on that server. Any bot that does not follow the rules could, in theory, be denied access to or removed from the affected website. If the posted text file has no associated program/software/app, then adhering to the rules i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meow Wars
The Meow Wars were an early example of a flame war sent over Usenet which began in 1996 and ended circa 1998. Its participants were known as "Meowers".Bartlett, Jamie.A Life Ruin: Inside the Digital Underworld" - Excerpt from: '' The Dark Net: Inside the Digital Underworld'' posted by Penguin Random House UK to Medium.com. Version on Google Books: Melville House Publishing, June 2, 2015. , 9781612194905. Google Books pages discussing the Meow Wars (using "Meowers" to describe the participants) arPT29anPT30/ref> The war was characterized by posters from one newsgroup "crapflooding", or posting a large volume of nonsense messages, to swamp on-topic communication in other groups. Ultimately, the flame war affected many boards, with Roisin Kiberd writing in ''Motherboard'', a division of ''Vice'', that esoteric Internet vocabulary was created as a result of the Meow Wars. The wars began when some Harvard students, who had "colonized" an abandoned newsgroup for fans of Karl Malden, , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trojan Horse (computing)
In computing, a trojan horse (or simply trojan; often capitalized, but see below) is a kind of malware that misleads users as to its true intent by disguising itself as a normal program. Trojans are generally spread by some form of social engineering (security), social engineering. For example, a user may be duped into executing an email attachment disguised to appear innocuous (e.g., a routine form to be filled in), or into clicking on a fake advertisement on the Internet. Although their payload can be anything, many modern forms act as a backdoor (computing), backdoor, contacting a controller who can then have unauthorized access to the affected device. Ransomware attacks are often carried out using a trojan. Unlike computer viruses and Computer worm, worms, trojans generally do not attempt to inject themselves into other files or otherwise propagate themselves. Origins of the term The term is derived from the Ancient Greece, ancient Greek story of the deceptive Trojan Horse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Worm
A computer worm is a standalone malware computer program that replicates itself in order to spread to other computers. It often uses a computer network to spread itself, relying on security failures on the target computer to access it. It will use this machine as a host to scan and infect other computers. When these new worm-invaded computers are controlled, the worm will continue to scan and infect other computers using these computers as hosts, and this behaviour will continue. Computer worms use recursive methods to copy themselves without host programs and distribute themselves based on exploiting the advantages of exponential growth, thus controlling and infecting more and more computers in a short time. Worms almost always cause at least some harm to the network, even if only by consuming bandwidth, whereas viruses almost always corrupt or modify files on a targeted computer. Many worms are designed only to spread, and do not attempt to change the systems they pass thro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Virus
A computer virus is a type of malware that, when executed, replicates itself by modifying other computer programs and Code injection, inserting its own Computer language, code into those programs. If this replication succeeds, the affected areas are then said to be "infected" with a computer virus, a metaphor derived from biological viruses. Computer viruses generally require a Computer program, host program. The virus writes its own code into the host program. When the program runs, the written virus program is executed first, causing infection and damage. By contrast, a computer worm does not need a host program, as it is an independent program or code chunk. Therefore, it is not restricted by the Computer program, host program, but can run independently and actively carry out attacks. Virus writers use social engineering (security), social engineering deceptions and exploit detailed knowledge of vulnerability (computing), security vulnerabilities to initially infect systems an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denial-of-service Attack
In computing, a denial-of-service attack (DoS attack) is a cyberattack in which the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a host connected to a network. Denial of service is typically accomplished by flooding the targeted machine or resource with superfluous requests in an attempt to overload systems and prevent some or all legitimate requests from being fulfilled. The range of attacks varies widely, spanning from inundating a server with millions of requests to slow its performance, overwhelming a server with a substantial amount of invalid data, to submitting requests with an illegitimate IP address. In a distributed denial-of-service attack (DDoS attack), the incoming traffic flooding the victim originates from many different sources. More sophisticated strategies are required to mitigate this type of attack; simply attempting to block a single source is insuffic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrashing (computer Science)
In computer science, thrashing occurs in a system with virtual memory when a computer's real storage resources are ''overcommitted'', leading to a constant state of paging and page faults, slowing most application-level processing. This causes the performance of the computer to degrade or even collapse. The situation can continue indefinitely until the user closes some running applications or the active processes free up additional virtual memory resources. After initialization, most programs operate on a small number of code and data pages compared to the total memory the program requires. The pages most frequently accessed at any point are called the working set, which may change over time. When the working set is not significantly greater than the system's total number of real storage ''page frames'', virtual memory systems work most efficiently, and an insignificant amount of computing is spent resolving page faults. As the total of the working sets grows, resolving page fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time-sharing
In computing, time-sharing is the Concurrency (computer science), concurrent sharing of a computing resource among many tasks or users by giving each Process (computing), task or User (computing), user a small slice of CPU time, processing time. This quick switch between tasks or users gives the illusion of Parallel computing, simultaneous execution. It enables computer multitasking, multi-tasking by a single user or enables multiple-user sessions. Developed during the 1960s, its emergence as the prominent model of computing in the 1970s represented a major technological shift in the history of computing. By allowing many users to interact concurrent computing, concurrently with a single computer, time-sharing dramatically lowered the cost of providing computing capability, made it possible for individuals and organizations to use a computer without owning one, and promoted the Interactive computing, interactive use of computers and the development of new interactive application ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Page Table
A page table is a data structure used by a virtual memory system in a computer to store mappings between virtual addresses and physical addresses. Virtual addresses are used by the program executed by the accessing process, while physical addresses are used by the hardware, or more specifically, by the random-access memory (RAM) subsystem. The page table is a key component of virtual address translation that is necessary to access data in memory. The page table is set up by the computer's operating system, and may be read and written during the virtual address translation process by the memory management unit or by low-level system software or firmware. Role of the page table In operating systems that use virtual memory, every process is given the impression that it is working with large, contiguous sections of memory. Physically, the memory of each process may be dispersed across different areas of physical memory, or may have been moved ( paged out) to secondary storage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spooling
In computing, spooling is a specialized form of multi-programming for the purpose of copying data between different devices. In contemporary systems, it is usually used for mediating between a computer application and a slow peripheral, such as a printer. Spooling allows programs to "hand off" work to be done by the peripheral and then proceed to other tasks, or to not begin until input has been transcribed. A dedicated program, the spooler, maintains an orderly sequence of jobs for the peripheral and feeds it data at its own rate. Conversely, for slow ''input'' peripherals, such as a card reader, a spooler can maintain a sequence of computational jobs waiting for data, starting each job when all of the relevant input is available; see batch processing. The spool itself refers to the sequence of jobs, or the storage area where they are held. In many cases, the spooler is able to drive devices at their full rated speed with minimal impact on other processing. Spooling is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
