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Real Time Linux
RTLinux is a hard realtime real-time operating system (RTOS) microkernel that runs the entire Linux operating system as a fully preemptive process. The hard real-time property makes it possible to control robots, data acquisition systems, manufacturing plants, and other time-sensitive instruments and machines from RTLinux applications. The design was patented. Despite the similar name, it is not related to the Real-Time Linux project of the Linux Foundation. RTLinux was developed by Victor Yodaiken, Michael Barabanov, Cort Dougan and others at the New Mexico Institute of Mining and Technology and then as a commercial product at FSMLabs. Wind River Systems acquired FSMLabs embedded technology in February 2007 and made a version available as Wind River Real-Time Core for Wind River Linux. As of August 2011, Wind River has discontinued the Wind River Real-Time Core product line, effectively ending commercial support for the RTLinux product. Background The key RTLinux design obj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Real-Time Linux
The Linux Foundation (LF) is a non-profit technology consortium founded in 2000 as a merger between Open Source Development Labs and the Free Standards Group to standardize Linux, support its growth, and promote its commercial adoption. Additionally, it hosts and promotes the collaborative development of open source software projects. It is a major force in promoting diversity and inclusion in both Linux and the wider open source software community. The foundation was launched in 2000, under the Open Source Development Labs (OSDL) and became the organization it is today when OSDL merged with the Free Standards Group (FSG). The Linux Foundation sponsors the work of Linux creator Linus Torvalds and lead maintainer Greg Kroah-Hartman. Furthermore, it is supported by members, such as AT&T, Cisco, Fujitsu, Google, Hitachi, Huawei, IBM, Intel, Meta, Microsoft, NEC, Oracle, Orange S.A., Qualcomm, Samsung, Tencent, and VMware, as well as developers from around the world. In recent y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multi-Environment Real-Time
Multi-Environment Real-Time (MERT), later renamed UNIX Real-Time (UNIX-RT), is a hybrid time-sharing and real-time operating system developed in the 1970s at Bell Labs for use in embedded minicomputers (especially PDP-11s). A version named Duplex Multi Environment Real Time (DMERT) was the operating system for the AT&T 3B20D telephone switching minicomputer, designed for high availability; DMERT was later renamed Unix RTR (Real-Time Reliable). A ''generalization'' of Bell Labs' time-sharing operating system Unix, MERT featured a redesigned, modular kernel that was able to run Unix programs and privileged real-time computing processes. These processes' data structures were isolated from other processes with message passing being the preferred form of interprocess communication (IPC), although shared memory was also implemented. MERT also had a custom file system with special support for large, contiguous, statically sized files, as used in real-time database applications. The desi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preemption (computing)
In computing, preemption is the act of temporarily interrupting an executing task, with the intention of resuming it at a later time. This interrupt is done by an external scheduler with no assistance or cooperation from the task. This preemptive scheduler usually runs in the most privileged protection ring, meaning that interruption and resuming are considered highly secure actions. Such a change in the currently executing task of a processor is known as context switching. User mode and kernel mode In any given system design, some operations performed by the system may not be preemptable. This usually applies to kernel functions and service interrupts which, if not permitted to run to completion, would tend to produce race conditions resulting in deadlock. Barring the scheduler from preempting tasks while they are processing kernel functions simplifies the kernel design at the expense of system responsiveness. The distinction between user mode and kernel mode, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenomai
Xenomai is a real-time development software framework cooperating with the Linux kernel to provide pervasive, interface-agnostic, hard real-time computing support to user space application software seamlessly integrated into the Linux environment. The Xenomai project was launched in August 2001. In 2003, it merged with the Real-Time Application Interface (RTAI) project to produce RTAI/fusion, a real-time free software platform for Linux on Xenomai's abstract real-time operating system (RTOS) core. Eventually, the RTAI/fusion effort became independent from RTAI in 2005 as the Xenomai project. Xenomai is based on an abstract RTOS core, usable for building any kind of real-time interface, over a nucleus which exports a set of generic RTOS services. Any number of RTOS personalities called “skins” can then be built over the nucleus, providing their own specific interface to the applications, by using the services of a single generic core to implement it. Xenomai vs. RTAI Many di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SCHED DEADLINE
SCHED_DEADLINE is a CPU scheduler available in the Linux kernel since version 3.14, Linux Weekly News, Deadline scheduling for Linux OSNews, Deadline Scheduling in the Linux Kernel based on the earliest deadline first scheduling, Earliest Deadline First (EDF) and Constant Bandwidth Server (CBS) L. Abeni and G. Buttazzo, "Integrating multimedia applications in hard real ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RMX (operating System)
Real-time Multitasking eXecutive (iRMX) is a real-time operating system designed for use with the Intel 8080 and 8086 family of processors. Overview Intel developed iRMX in the 1970s and originally released RMX/80 in 1976 and RMX/86 in 1980 to support and create demand for their processors and Multibus system platforms. The functional specification for RMX/86 was authored by Bruce Schafer and Miles Lewitt and was completed in the summer of 1978 soon after Intel relocated the entire Multibus business from Santa Clara, California to Aloha, Oregon. Schafer and Lewitt went on each manage one of the two teams that developed the RMX/86 product for release on schedule in 1980. Effective 2000 iRMX is supported, maintained, and licensed worldwide by TenAsys Corporation, under an exclusive licensing arrangement with Intel. iRMX is a layered design: containing a kernel, nucleus, basic i/o system, extended i/o system and human interface. An installation need include only the components ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RTAI
Real-time application interface (RTAI) is a real-time extension for the Linux kernel, which lets users write applications with strict timing constraints for Linux. Like Linux itself the RTAI software is a community effort. RTAI provides deterministic response to interrupts, POSIX-compliant and native RTAI real-time tasks. RTAI supports several architectures, including IA-32 (with and without FPU and TSC), x86-64, PowerPC, ARM (StrongARM and ARM7: clps711x-family, Cirrus Logic EP7xxx, CS89712, PXA25x), and MIPS. RTAI consists mainly of two parts: an Adeos-based patch to the Linux kernel which introduces a hardware abstraction layer, and a broad variety of services which make lives of real-time programmers easier. RTAI versions over 3.0 use an Adeos kernel patch, slightly modified in the x86 architecture case, providing additional abstraction and much lessened dependencies on the "patched" operating system. Adeos is a kernel patch comprising an Interrupt Pipeline where dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kernel Module
In computing, a loadable kernel module (LKM) is an object file that contains code to extend the running kernel, or so-called ''base kernel'', of an operating system. LKMs are typically used to add support for new hardware (as device drivers) and/or filesystems, or for adding system calls. When the functionality provided by an LKM is no longer required, it can be unloaded in order to free memory and other resources. Most current Unix-like systems and Microsoft Windows support loadable kernel modules under different names, such as kernel loadable module (kld) in FreeBSD, kernel extension (kext) in macOS (although support for third-party modules is being dropped), kernel extension module in AIX, kernel-mode driver in Windows NT and downloadable kernel module (DKM) in VxWorks. They are also known as kernel loadable modules (or KLM), and simply as kernel modules (KMOD). Advantages Without loadable kernel modules, an operating system would have to include all possible anticipated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FIFO (computing And Electronics)
Representation of a FIFO queue In computing and in systems theory, FIFO is an acronym for first in, first out (the first in is the first out), a method for organizing the manipulation of a data structure (often, specifically a data buffer) where the oldest (first) entry, or "head" of the queue, is processed first. Such processing is analogous to servicing people in a queue area on a first-come, first-served (FCFS) basis, i.e. in the same sequence in which they arrive at the queue's tail. FCFS is also the jargon term for the FIFO operating system scheduling algorithm, which gives every process central processing unit (CPU) time in the order in which it is demanded. FIFO's opposite is LIFO, last-in-first-out, where the youngest entry or "top of the stack" is processed first. A priority queue is neither FIFO or LIFO but may adopt similar behaviour temporarily or by default. Queueing theory encompasses these methods for processing data structures, as well as interactions b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
POSIX Threads
POSIX Threads, commonly known as pthreads, is an execution model that exists independently from a language, as well as a parallel execution model. It allows a program to control multiple different flows of work that overlap in time. Each flow of work is referred to as a ''thread'', and creation and control over these flows is achieved by making calls to the POSIX Threads API. POSIX Threads is an API defined by the standard ''POSIX.1c, Threads extensions (IEEE Std 1003.1c-1995)''. Implementations of the API are available on many Unix-like POSIX-conformant operating systems such as FreeBSD, NetBSD, OpenBSD, Linux, macOS, Android, Solaris, Redox, and AUTOSAR Adaptive, typically bundled as a library libpthread. DR-DOS and Microsoft Windows implementations also exist: within the SFU/SUA subsystem which provides a native implementation of a number of POSIX APIs, and also within third-party packages such as ''pthreads-w32'', which implements pthreads on top of existing Windows API ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
POSIX
The Portable Operating System Interface (POSIX) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. POSIX defines both the system- and user-level application programming interfaces (APIs), along with command line shells and utility interfaces, for software compatibility (portability) with variants of Unix and other operating systems. POSIX is also a trademark of the IEEE. POSIX is intended to be used by both application and system developers. Name Originally, the name "POSIX" referred to IEEE Std 1003.1-1988, released in 1988. The family of POSIX standards is formally designated as IEEE 1003 and the ISO/IEC standard number is ISO/ IEC 9945. The standards emerged from a project that began in 1984 building on work from related activity in the ''/usr/group'' association. Richard Stallman suggested the name ''POSIX'' (pronounced as ''pahz-icks,'' as in ''positive'', not as ''poh-six'') to the IEEE instead of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loadable Kernel Module
In computing, a loadable kernel module (LKM) is an object file that contains code to extend the running kernel, or so-called ''base kernel'', of an operating system. LKMs are typically used to add support for new hardware (as device drivers) and/or filesystems, or for adding system calls. When the functionality provided by an LKM is no longer required, it can be unloaded in order to free memory and other resources. Most current Unix-like systems and Microsoft Windows support loadable kernel modules under different names, such as kernel loadable module (kld) in FreeBSD, kernel extension (kext) in macOS (although support for third-party modules is being dropped), kernel extension module in AIX, kernel-mode driver in Windows NT and downloadable kernel module (DKM) in VxWorks. They are also known as kernel loadable modules (or KLM), and simply as kernel modules (KMOD). Advantages Without loadable kernel modules, an operating system would have to include all possible anticipa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
