QNX


QNX is a commercial Unix-like real-time operating system, aimed primarily at the embedded systems market. QNX was one of the first commercially successful microkernel operating systems., it is used in a variety of devices including cars and mobile phones.
The product was originally developed in the early 1980s by Canadian company Quantum Software Systems, later renamed QNX Software Systems. The company was ultimately acquired by BlackBerry Limited in 2010.

Description

As a microkernel-based OS, QNX is based on the idea of running most of the operating system kernel in the form of a number of small tasks, named Resource Managers. This differs from the more traditional monolithic kernel, in which the operating system kernel is one very large program composed of a huge number of parts, with special abilities. In the case of QNX, the use of a microkernel allows users to turn off any functions they do not need without having to change the OS. Instead, such services will simply not run.
The system is quite small, with earlier versions fitting on one 1.44 MB floppy disk.
QNX Neutrino has been ported to a number of platforms and now runs on practically any modern central processing unit family that is used in the embedded market. This includes the PowerPC, x86, MIPS, SH-4, and the closely interrelated of ARM, StrongARM, and XScale.
QNX offers a license for noncommercial and academic users.
The BlackBerry PlayBook tablet computer designed by BlackBerry uses a version of QNX as the primary operating system. Devices from BlackBerry running the BlackBerry 10 operating system are also based on QNX.
QNX is also used in car infotainment systems with many major car makers offering variants that include an embedded QNX architecture. It is supported by popular SSL/TLS libraries such as wolfSSL.

History

and Dan Dodge, both students at the University of Waterloo in 1980, took a course in real-time operating systems, in which the students constructed a basic real-time microkernel and user programs. Both were convinced there was a commercial need for such a system, and moved to the high-tech planned community Kanata, Ontario, to start Quantum Software Systems that year. In 1982, the first version of QUNIX was released for the Intel 8088 CPU. In 1984, Quantum Software Systems renamed QUNIX to QNX in an effort to avoid any trademark infringement challenges.
One of the first widespread uses of the QNX real-time OS was in the nonembedded world when it was selected as the operating system for the Ontario education system's own computer design, the Unisys ICON. Over the years QNX was used mostly for larger projects, as its 44k kernel was too large to fit inside the one-chip computers of the era. The system garnered a reputation for reliability and became used in running machinery in many industrial applications.
In the late-1980s, Quantum realized that the market was rapidly moving towards the Portable Operating System Interface model and decided to rewrite the kernel to be much more compatible at a low level. The result was QNX 4. During this time Patrick Hayden, while working as an intern, along with Robin Burgener, developed a new windowing system. This patented concept was developed into the embeddable graphical user interface named the QNX Photon microGUI. QNX also provided a version of the X Window System.
Toward the end of the 1990s, the company began work on a new version of QNX, designed from the ground up to be symmetric multiprocessing capable, and to support all current POSIX application programming interfaces and any new POSIX APIs that could be anticipated while still retaining the microkernel architecture. This resulted in QNX Neutrino, released in 2001.
Along with the Neutrino kernel, QNX Software Systems became a founding member of the Eclipse consortium. The company released a suite of Eclipse plug-ins packaged with the Eclipse workbench in 2002, and named QNX Momentics Tool Suite.
In 2004, the company announced it had been sold to Harman International Industries. Before this acquisition, QNX software was already widely used in the automotive industry for telematics systems. Since the purchase by Harman, QNX software has been designed into over 200 different automobile makes and models, in telematics systems and in infotainment and navigation units. The QNX CAR Application Platform was running in over 20 million vehicles as of mid-2011. The company has since released several middleware products including the QNX Aviage Multimedia Suite, the QNX Aviage Acoustic Processing Suite and the QNX HMI Suite.
The microkernels of Cisco Systems' IOS-XR and IOS Software Modularity are based upon QNX.
In September 2007, QNX Software Systems announced the availability of some of its source code.
On April 9, 2010, Research In Motion announced they would acquire QNX Software Systems from Harman International Industries. On the same day, QNX source code access was restricted from the public and hobbyists.
In September 2010, the company announced a tablet computer, the BlackBerry PlayBook, and a new operating system BlackBerry Tablet OS based on QNX to run on the tablet.
On October 18, 2011, Research In Motion announced "BBX", which was later renamed to BlackBerry 10, in December 2011. Blackberry 10 devices build upon the BlackBerry PlayBook QNX based operating system for touch devices, but adapt the user interface for smartphones using the Qt based Cascades Native User-Interface framework.
At the Geneva Motor Show, Apple demonstrated CarPlay which provides an iOS-like user interface to head units in compatible vehicles. Once configured by the automaker, QNX can be programmed to hand off its display and some functions to an Apple CarPlay device.
On December 11, 2014, Ford Motor Company stated the company would be replacing Microsoft Auto with QNX.
In January 2017, QNX announced the upcoming release of its SDP 7.0, with support for Intel and ARM 32- and 64-bit platforms, and support for C++14; it was released in March 2017.

Technology

The QNX kernel, procnto, contains only CPU scheduling, interprocess communication, interrupt redirection and timers. Everything else runs as a user process, including a special process known as proc which performs process creation and memory management by operating in conjunction with the microkernel. This is made possible by two key mechanisms: subroutine-call type interprocess communication, and a boot loader which can load an image containing the kernel and any desired set of user programs and shared libraries. There are no device drivers in the kernel. The network stack is based on NetBSD code. Along with its support for its own, native, device drivers, QNX supports its legacy, io-net manager server, and the network drivers ported from NetBSD.
QNX interprocess communication consists of sending a message from one process to another and waiting for a reply. This is a single operation, called MsgSend. The message is copied, by the kernel, from the address space of the sending process to that of the receiving process. If the receiving process is waiting for the message, control of the CPU is transferred at the same time, without a pass through the CPU scheduler. Thus, sending a message to another process and waiting for a reply does not result in "losing one's turn" for the CPU. This tight integration between message passing and CPU scheduling is one of the key mechanisms that makes QNX message passing broadly usable. Most Unix and Linux interprocess communication mechanisms lack this tight integration, although a user space implementation of QNX-type messaging for Linux does exist. Mishandling of this subtle issue is a primary reason for the disappointing performance of some other microkernel systems such as early versions of Mach. The recipient process need not be on the same physical machine.
All I/O operations, file system operations, and network operations were meant to work through this mechanism, and the data transferred was copied during message passing. Later versions of QNX reduce the number of separate processes and integrate the network stack and other function blocks into single applications for performance reasons.
Message handling is prioritized by thread priority. Since I/O requests are performed using message passing, high priority threads receive I/O service before low priority threads, an essential feature in a hard real-time system.
The boot loader is the other key component of the minimal microkernel system. Because user programs can be built into the boot image, the set of device drivers and support libraries needed for startup need not be, and are not, in the kernel. Even such functions as program loading are not in the kernel, but instead are in shared user-space libraries loaded as part of the boot image. It is possible to put an entire boot image into ROM, which is used for diskless embedded systems.
Neutrino supports symmetric multiprocessing and processor affinity, called bound multiprocessing in QNX terminology. BMP is used to improve cache hitting and to ease the migration of non-SMP safe applications to multi-processor computers.
Neutrino supports strict priority-preemptive scheduling and adaptive partition scheduling. APS guarantees minimum CPU percentages to selected groups of threads, even though others may have higher priority. The adaptive partition scheduler is still strictly priority-preemptive when the system is underloaded. It can also be configured to run a selected set of critical threads strictly real time, even when the system is overloaded.

QNX RTOS Release history

QNX RTOS History
VersionDateDistribution mediumNotes
1981QUNIX Founded.
Beta1983As QNX Beta
1.01984
2.01987Elements of 4.3BSD like TCP/IP and PPP merged into QNX 2.0.
2.211989QNX 2.21
4.01990QNX 4.0
4.11994Elements of 4.4BSD into QNX 4.1
4.21995QNX 4.2
4.221995QNX 4.22
4.241995QNX/Neutrino 1.0 is forked from QNX 4.24
4.251997QNX 4.25 continues after fork with QNX/Neutrino 1.0.

QNX/Neutrino Release history

QNX/Neutrino Microkernel history -- Forked from QNX 4.24 in 1996.
ReleaseDateEnd-of-LifeNotes
1.01996QNX/Neutrino 1.0 as forked from QNX 4.24
2.01998QNX/Neutrino 2.0
2.101999QNX/Neutrino 2.10
2.101998
6January 18, 2001QNX RTOS 6
6.1.02001QNX RTOS 6
6.1.0 Patch September 28, 2001
6.2June 4, 2002QNX 6.2
6.2 October 18, 2002February 2010QNX 6.2
6.2.1February 18, 2003June 2010QNX 6.2.1
6.3June 3, 2004June 2011QNX 6.3
6.3.0 SP1?June 2012
6.3.0 SP2?November 2012
6.3.0 SP3 / OS 6.3.2November 2013
6.3.2October 2014
6.4.0October 30, 2008November 2015QNX Neutrino RTOS 6.4.0
6.4.1May 2009June 2016QNX Neutrino RTOS 6.4.1
6.5.0July 2010August 2017QNX Neutrino RTOS 6.5.0 is forked to produce BBX, as announced on October 18, 2011, and later previewed, named "BlackBerry 10 OS" on May 1, 2012.
6.5 SP1July 11, 2012June 2019QNX Neutrino RTOS 6.5 SP1
6.6February 28, 2014March 2021QNX 6.6
7.0January 4, 2017March 2024QNX SDP 7.0
7.1July 23, 2020QNX SDP 7.1

Transparent Distributed Processing

Due to its microkernel architecture QNX is also a distributed operating system. Dan Dodge and Peter van der Veen hold based on the QNX operating system's distributed processing features known commercially as Transparent Distributed Processing. This allows the QNX kernels on separate devices to access each other's system services using effectively the same communication mechanism as is used to access local services.

Forums

OpenQNX is a QNX Community Portal established and run independently. An IRC channel and Newsgroups access via web is available. Diverse industries are represented by the developers on the site.
Foundry27 is a web-based QNX community established by the company. It serves as a hub to QNX Neutrino development where developers can register, choose the license, and get the source code and related toolkit of the RTOS.

Reception

PC Magazine stated in April 1983 that QNX was "an extraordinary piece of software". Citing its multitasking, the review concluded that "QNX gives you the power to maximize utilization of the PC's resources".