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Ingo Molnár
Ingo Molnár, employed by Red Hat as of May 2013, is a Hungarian Linux hacker. He is known for his contributions to the operating system in terms of security and performance. Life and career Molnár studied at Eötvös Loránd University. Work Some of his additions to the Linux kernel include the O(1) scheduler of Linux-2.6.0 and the Completely Fair Scheduler of Linux-2.6.23, the in-kernel TUX HTTP / FTP server, as well as his work to enhance thread handling. He also wrote a kernel security feature called "Exec Shield", which prevents stack-based buffer overflow exploits in the x86 architecture by disabling the execute permission for the stack. Together with Thomas Gleixner, he worked on the real-time preemption (PREEMPT_RT) patch set, which aims to reduce the maximum thread switching latency of the Linux kernel from an unbounded number of milliseconds to down to bounded values in the order of tens of microseconds (depending on the system). As of 2011, Thomas Gleixner is wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Completely Fair Scheduler
The Completely Fair Scheduler (CFS) is a process scheduler that was merged into the 2.6.23 (October 2007) release of the Linux kernel and is the default scheduler of the tasks of the SCHED_NORMAL class (i.e., tasks that have no real-time execution constraints). It handles CPU resource allocation for executing processes, and aims to maximize overall CPU utilization while also maximizing interactive performance. In contrast to the previous O(1) scheduler used in older Linux 2.6 kernels, which maintained and switched run queues of active and expired tasks, the CFS scheduler implementation is based on per-CPU run queues, whose nodes are time-ordered schedulable entities that are kept sorted by red–black trees. The CFS does away with the old notion of per-priorities fixed time-slices and instead it aims at giving a fair share of CPU time to tasks (or, better, schedulable entities). Algorithm A task (i.e., a synonym for thread) is the minimal entity that Linux can schedule. Howeve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buffer Overflow
In information security and programming, a buffer overflow, or buffer overrun, is an anomaly whereby a program, while writing data to a buffer, overruns the buffer's boundary and overwrites adjacent memory locations. Buffers are areas of memory set aside to hold data, often while moving it from one section of a program to another, or between programs. Buffer overflows can often be triggered by malformed inputs; if one assumes all inputs will be smaller than a certain size and the buffer is created to be that size, then an anomalous transaction that produces more data could cause it to write past the end of the buffer. If this overwrites adjacent data or executable code, this may result in erratic program behavior, including memory access errors, incorrect results, and crashes. Exploiting the behavior of a buffer overflow is a well-known security exploit. On many systems, the memory layout of a program, or the system as a whole, is well defined. By sending in data designed to ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Independent Software Vendor
An independent software vendor (ISV), also known as a software publisher, is an organization specializing in making and selling software, as opposed to computer hardware, designed for mass or niche markets. This is in contrast to in-house software, which is developed by the organization that will use it, or custom software, which is designed or adapted for a single, specific third party. Although ISV-provided software is consumed by end users, it remains the property of the vendor. Software products developed by ISVs serve a wide variety of purposes. Examples include software for real estate brokers, scheduling for healthcare personnel, barcode scanning, stock maintenance, gambling, retailing, energy exploration, vehicle fleet management, and child care management software. An ISV makes and sells software products that run on one or more computer hardware or operating system platforms. Companies that make the platforms, such as Microsoft, AWS, Cisco, IBM, Hewlett-Packard, Red Hat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platform (computing)
A computing platform or digital platform is an environment in which a piece of software is executed. It may be the hardware or the operating system (OS), even a web browser and associated application programming interfaces, or other underlying software, as long as the program code is executed with it. Computing platforms have different abstraction levels, including a computer architecture, an OS, or runtime libraries. A computing platform is the stage on which computer programs can run. A platform can be seen both as a constraint on the software development process, in that different platforms provide different functionality and restrictions; and as an assistant to the development process, in that they provide low-level functionality ready-made. For example, an OS may be a platform that abstracts the underlying differences in hardware and provides a generic command for saving files or accessing the network. Components Platforms may also include: * Hardware alone, in the case o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AppImage
AppImage is a format for distributing portable software on Linux without needing superuser permissions to install the application. It tries also to allow Linux distribution-agnostic binary software deployment for application developers, also called upstream packaging. Released first in 2004 under the name klik, it was continuously developed, then renamed in 2011 to PortableLinuxApps and later in 2013 to AppImage. Description Objectives AppImage aims to be an application deployment system for Linux with the following objectives: simplicity, binary compatibility, distro agnosticism, no installation, no root permission, being portable, and keeping the underlying operating system untouched. Properties AppImage does not install the application in the traditional Linux sense. Instead of putting the application's various files in the distro's appropriate places in the file system, the AppImage file is just the application's compressed image. When it runs, the file is mounted with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zero Install
Zero Install is a means of distributing and packaging software for multiple operating systems (Unix-like including Linux and macOS, Windows). Software Rather than the normal method of downloading a software package, extracting it, and installing it before it can be used (with the accompanying use of destructive updates and privilege escalation), packages distributed using Zero Install only need be run. The first time software is accessed, it is downloaded from the Internet and cached; subsequently, software is accessed from the cache. Inside the cache, each application unpacks to its own directory, as in Application Directory systems. The system is intended to be used alongside a distribution's native package manager. Two advantages of Zero Install over more popular packaging systems are that it is cross-platform and no root password is needed to install software; packages can be installed in system locations writable by that user instead of requiring administrator access. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autopackage
Autopackage is a free computer package management system aimed at making it simple to create a package that can be installed on all Linux distributions, created by Mike Hearn around 2002. In August 2010, Listaller and Autopackage announced that the projects will merge. Projects such as aMSN and Inkscape offered an Autopackage installer, and Freecode offered content submitters a field to put the URL of Autopackages. The list of available packages is very limited, and most program versions are obsolete (for example, the most recent Autopackage of GIMP is 2.2.6, even though GIMP is now at version 2.8.2, as of August 2012). Methodology Autopackage was designed for installing binary, or pre-compiled, versions of non-core applications such as word processors, web browsers, and personal computer games, rather than core libraries and applications such as operating system shells. Concept of autopackage was to "improve" Linux to a desktop platform, with stable binary interfaces compara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linux Distribution
A Linux distribution (often abbreviated as distro) is an operating system made from a software collection that includes the Linux kernel and, often, a package management system. Linux users usually obtain their operating system by downloading one of the Linux distributions, which are available for a wide variety of systems ranging from embedded devices (for example, OpenWrt) and personal computers (for example, Linux Mint) to powerful supercomputers (for example, Rocks Cluster Distribution). A typical Linux distribution comprises a Linux kernel, GNU tools and libraries, additional software, documentation, a window system (the most common being the X Window System, or, more recently, Wayland), a window manager, and a desktop environment. Most of the included software is free and open-source software made available both as compiled binaries and in source code form, allowing modifications to the original software. Usually, Linux distributions optionally include some proprietary so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linux Desktop
Besides the Linux distributions designed for general-purpose use on desktops and servers, distributions may be specialized for different purposes including computer architecture support, embedded systems, stability, security, localization to a specific region or language, targeting of specific user groups, support for real-time applications, or commitment to a given desktop environment. Furthermore, some distributions deliberately include only free software. , over four hundred Linux distributions are actively developed, with about a dozen distributions being most popular for general-purpose use. Desktop The popularity of Linux on standard desktop computers and laptops has been increasing over the years. Most modern distributions include a graphical user environment, with, , the three most popular environments being the KDE Plasma Desktop, Xfce and GNOME. No single official Linux desktop exists: rather desktop environments and Linux distributions select components from a poo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scheduling (computing)
In computing, scheduling is the action of assigning ''resources'' to perform ''tasks''. The ''resources'' may be processors, network links or expansion cards. The ''tasks'' may be threads, processes or data flows. The scheduling activity is carried out by a process called scheduler. Schedulers are often designed so as to keep all computer resources busy (as in load balancing), allow multiple users to share system resources effectively, or to achieve a target quality-of-service. Scheduling is fundamental to computation itself, and an intrinsic part of the execution model of a computer system; the concept of scheduling makes it possible to have computer multitasking with a single central processing unit (CPU). Goals A scheduler may aim at one or more goals, for example: * maximizing ''throughput'' (the total amount of work completed per time unit); * minimizing '' wait time'' (time from work becoming ready until the first point it begins execution); * minimizing '' latency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Con Kolivas
Con Kolivas is an Australian anaesthetist.Anaesthesia Information Page by Kolivas, Jan 2001 He has worked as a on the and on the development of the cryptographic currency mining software CGMiner.CGMiner GitHub repository, "ASIC and FPGA miner in c for bitcoin" /ref> His Linux contributions include |
Thread Switching Latency
In computing, a context switch is the process of storing the state of a process or thread, so that it can be restored and resume execution at a later point, and then restoring a different, previously saved, state. This allows multiple processes to share a single central processing unit (CPU), and is an essential feature of a multitasking operating system. The precise meaning of the phrase "context switch" varies. In a multitasking context, it refers to the process of storing the system state for one task, so that task can be paused and another task resumed. A context switch can also occur as the result of an interrupt, such as when a task needs to access disk storage, freeing up CPU time for other tasks. Some operating systems also require a context switch to move between user mode and kernel mode tasks. The process of context switching can have a negative impact on system performance. Cost Context switches are usually computationally intensive, and much of the design of oper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
