News Archive (1999-2012) | 2013-current at LinuxGizmos | Current Tech News Portal |    About   

Hypervisor targets embedded multi-core

Jun 15, 2009 — by Eric Brown — from the LinuxDevices Archive — 9 views

Wind River announced the availability of its long-awaited virtualization technology for networking and industrial embedded systems. Wind River Hypervisor supports Intel and PowerPC multi-core processors running Wind River Linux and VxWorks, and will eventually support other chip architectures and operating systems (OSes), says the company.

The Wind River Hypervisor was announced a year ago, and is now widely seen as one of the key technological components that led Intel to make its recent $884 million acquisition bid for the company. Wind River Hypervisor is closely integrated with the other technology of particular interest to Intel: enhanced multi-core support in the company's VxWorks real-time operating system (RTOS) and Wind River Linux 3.0 distributions.

Earlier this year, Intel and Wind River announced they would jointly market multi-core solutions based on Wind River Linux, VxWorks, and the new virtualization technology tuned to Intel architecture processors. Initial targeted markets were said to include aerospace and defense, network infrastructure, industrial, medical, and print imaging segments.

Wind River Hypervisor, simplified architecture

Type-1 personality

The Wind River Hypervisor is designed to enable embedded developers to replace multiple boards or CPUs with a single board or CPU, thereby saving on cost and power consumption, says Wind River. Developers can also use the technology to create devices that leverage multiple OSes, and reduce complexity when integrating multi-core processors.

The technology is billed as a “Type-1” hypervisor supporting real-time features including fast performance, low latency, determinism, and minimal footprint. The technology offers protection between OSes and cores, and is capable of starting, stopping, and reloading OSes for increased reliability, says the company. The technology is said to support Symmetric Multiprocessing (SMP), Asymmetric Multiprocessing (AMP) and supervised AMP architectures (see diagram below).

Wind River Hypervisor using supervised AMP architecture; WR NAE refers to Wind River network acceleration engines; WRE stands for Wind River Executive.
(Click to enlarge)

The Wind River Workbench integrated development environment (IDE) and toolsuite has now been extended to support developing software that runs on the hypervisor, says the company. Support is said to extend to prototype and simulation, system monitoring and analysis, debugging multiple contexts, and on-chip debugging.

Turning the knobs on embedded virtualization

While the Wind River Hypervisor supports running multiple OS instances on a single processor core, multi-core virtualization is the main focus, said Tomas Evensen, CTO of Wind River, in an interview.

“We offer an embedded focus where developers can really turn the knobs back and forth to get the maximum performance,” said Evensen. In addition, the Hypervisor is said to be tightly integrated with Wind River Linux, VxWorks, and their similar Workbench toolsuites. “We stand out from other virtualization solutions in that we offer the hypervisor, middleware, and tools all working really closely together,” said Evensen. “We give users control over both the software stack and virtualization, so it's fully optimized and integrated.”

Evensen also touted the technology for its scalability, customizability, and paravirtualization capabilities. Wind River Hypervisor provides greater flexibility for developers in deciding exactly where they want to settle on the “performance vs. protection” (security) trade-off, he said.

A cross-platform promise

While initially targeting Intel and PowerPC -architecture processors, the latter primarily from Wind River's long-time partner Freescale Semiconductor, the Hypervisor will eventually support MIPS and ARM platforms, said Evensen. Although some have speculated that Intel will scale back Wind River's support for non-Intel architectures, “business as usual” does indeed appear to be the current plan, according to Evensen.

“Going forward, we will have very broad support for multiple architectures on the Hypervisor,” he said. “Intel has been supporting this very early on, so they have a little bit of a lead, but if you look at the installed base of multi-core systems running on Wind River platforms, PowerPC is a very big part of that.”

Born to be embedded

Wind River Hypervisor is similar in features to server-oriented virtualization solutions from companies like VMWare, said Evensen, but is designed from scratch with embedded devices running on multi-core devices. That means a greater attention to performance and efficient operations.

“In a typical virtualization solution, a full OS like Linux runs on the bottom, with a hypervisor within or on top of the OS, and another OS sitting on top of that,” said Evensen. “So when a guest wants to do something like make a call to Ethernet, it has to call down to the host OS, which reduces performance. It works this way because the focus is on backward compatibility, but in the embedded space, backward compatibility is not that important. With devices, you can recompile and reconfigure differently. What is important in embedded is performance, so instead we let developers map Ethernet upwards so you don't have to waste time going to the host OS.”

A number of customers are already working with Wind River Hypervisor, said Evensen. About 70 percent of current and prospective customers want to run different OSes on different cores, said Evensen. Typical applications include a system where Linux resides on one core, taking care of the human interface, and VxWorks or another RTOS handles mission critical secure operations on another. Wind River is focusing on projects where either Linux or VxWorks is used, and typically the two OSes are paired. In other cases, the Hypervisor is used to maintain legacy code in an old proprietary RTOS or old version of VxWorks. This legacy partition is then matched with a new Linux or VxWorks OS in the other partition.

One automotive customer is said to be using the Hypervisor in a dashboard system. Although the system is primarily controlled by Linux, the developers wanted a faster booting RTOS to quickly bring up the display and start talking to the energy control system after ignition while Linux was still booting, said Evensen. The RTOS also handles communications over the car's CAN bus. The Hypervisor's job in devices like this is to play the role of a supervisor, keeping the two OSes securely separated in their own partitions while coordinating use of common resources between them.

The Workbench support is a key draw for embedded developers looking for a virtualization product, said Evensen. “With multi-core virtualization, testing tools become more important,” he said. “Multi-core is harder to debug, and you can get into timing problems. Workbench has a whole set of profiling tools, breakpoints, event loggers, and on-chip debugging tools that have been expanded for multi-core and virtualization.”


Wind River Hypervisor is available now for Linux and VxWorks on Intel and PowerPC architectures, says Wind River. More information may be found here and here.

Wind River also announced version 2.0 of its VxWorks MILS Platform 2.0 today, offering specific support for the Wind River Hypervisor.

This article was originally published on and has been donated to the open source community by QuinStreet Inc. Please visit for up-to-date news and articles about Linux and open source.

Comments are closed.