RTLinux
Encyclopedia
RTLinux or RTCore is a hard realtime RTOS
microkernel
that runs the entire Linux
operating system
as a fully preemptive
process.
It was developed by Victor Yodaiken (Yodaiken 1999), Michael Barabanov (Barabanov 1996), 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 now makes a version available as Wind River Real-Time Core for Wind River Linux.
RTLinux was based on a lightweight virtual machine where the Linux "guest" was given a virtualized interrupt
controller and timer - and all other hardware access was direct. From the point of view of the real-time "host", the Linux kernel is a thread. Interrupts needed for deterministic processing are processed by the real-time core, while other interrupts are forwarded to Linux, which runs at a lower priority than realtime threads. Linux drivers handle almost all I/O
. First-In-First-Out pipes (FIFO
s) or shared memory can be used to share data between the operating system and RTCore.
Real-time operating system
A real-time operating system is an operating system intended to serve real-time application requests.A key characteristic of a RTOS is the level of its consistency concerning the amount of time it takes to accept and complete an application's task; the variability is jitter...
microkernel
Microkernel
In computer science, a microkernel is the near-minimum amount of software that can provide the mechanisms needed to implement an operating system . These mechanisms include low-level address space management, thread management, and inter-process communication...
that runs the entire Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
as a fully preemptive
Preemption (computing)
In computing, preemption is the act of temporarily interrupting a task being carried out by a computer system, without requiring its cooperation, and with the intention of resuming the task at a later time. Such a change is known as a context switch...
process.
It was developed by Victor Yodaiken (Yodaiken 1999), Michael Barabanov (Barabanov 1996), Cort Dougan and others at the New Mexico Institute of Mining and Technology
New Mexico Institute of Mining and Technology
New Mexico Institute of Mining and Technology is a university located in Socorro, New Mexico....
and then as a commercial product at FSMLabs. Wind River Systems
Wind River Systems
Wind River Systems, Inc. is a company providing embedded systems, development tools for embedded systems, middleware, and other types of software. The company was founded in Berkeley, California in 1981 by Jerry Fiddler and David Wilner. On June 4, 2009, Wind River announced that Intel had bought...
acquired FSMLabs embedded technology in February 2007 and now makes a version available as Wind River Real-Time Core for Wind River Linux.
RTLinux was based on a lightweight virtual machine where the Linux "guest" was given a virtualized interrupt
controller and timer - and all other hardware access was direct. From the point of view of the real-time "host", the Linux kernel is a thread. Interrupts needed for deterministic processing are processed by the real-time core, while other interrupts are forwarded to Linux, which runs at a lower priority than realtime threads. Linux drivers handle almost all I/O
I/O
I/O may refer to:* Input/output, a system of communication for information processing systems* Input-output model, an economic model of flow prediction between sectors...
. First-In-First-Out pipes (FIFO
FIFO
FIFO is an acronym for First In, First Out, an abstraction related to ways of organizing and manipulation of data relative to time and prioritization...
s) or shared memory can be used to share data between the operating system and RTCore.
See also
- RTAIRTAIRTAI stands for Real-Time Application Interface. It is a real-time extension for the Linux kernel - which lets you write applications with strict timing constraints for Linux...
- alternative real-time extension for Linux kernel - iRMX for Windows - Real-time extension for Windows, somewhat similar architecturally.
- XenomaiXenomaiXenomai is a real-time development framework cooperating with the Linux kernel, to provide a pervasive, interface-agnostic, hard real-time support to user space applications, seamlessly integrated into the Linux environment....
- another alternative real-time extension for Linux kernel
External links
- FSMLabs, the original supplier of RTLinux
- Yodaiken's web page
- Article about RTLinux synchronization
- RTLinux Manifesto
- Real-time Linux Wiki
- http://www.soe.ucsc.edu/~sbrandt/courses/Winter00/290S/rtlinux.pdf
- Article about RT concept
- RTLinuxFree, open source (GPL with licensed patent) version offered by Wind River Systems
- Wind River Systems, supplier of RTLinuxPro / Wind River Real-Time Core - commercial versions of RTLinux