Canonical announces real-time Ubuntu kernel:
Real-time Ubuntu 22.04 LTS is now generally available. The new kernel supports low-latency requirements for industrial, telecommunications, automotive, aerospace and defense industries.
The real-time Ubuntu 22.04 LTS from publisher Canonical was released on Tuesday, Feb. 14, 2023. Enterprises running the open source operating system can now run more demanding workloads and develop a wide range of time-sensitive applications, Canonical said.
As a real-time solution, it was designed to minimize the response time guarantee within a specified deadline. With a new enterprise-grade real-time kernel, Ubuntu 22.04 LTS can keep up with stringent low-latency requirements such as smart factory applications.
The newest release is based on the 5.15 version of the Linux kernel. It includes Arm architecture and the out-of-tree PREEMPT_RT patches for x86, which reduces kernel latencies. Arm has a part in projects like software-defined vehicles, smart industrial 4.0 factories, 5G vRAN functionality and energy-efficient Arm-based hyperscale data centers.
"The commercial availability of real-time Ubuntu on Arm demonstrates the power of open source collaboration and benefits the entire Arm ecosystem across the computing spectrum, from cloud to edge," said Mark Hambleton, vice president of open source software at Arm.
[...] The real-time kernel can be applied across Ubuntu variants, and it has two options for deployment, Canonical said. The first option, Ubuntu Server 22.04 LTS, is available through the Ubuntu Pro subscription service. A free tier is available for personal and small-scale commercial use.
Enterprise customers can also access Ubuntu Core 22 with the real-time kernel through Canonical's IoT App Store. This version is the fully containerized Ubuntu variant optimized for edge devices. It includes state-of-the-art security features, from full-disk encryption to strict confinement.
Ubuntu emphasized that upgrades are not limited to patches and occasional bug fixes. Instead, the Ubuntu Core is designed to have a lifetime of a decade, getting robust software updates throughout.
(Score: 3, Informative) by Runaway1956 on Thursday February 16, @12:04AM (1 child)
Or - maybe not. RedHat has been doing this for awhile - https://www.redhat.com/sysadmin/real-time-kernel [redhat.com] - among others.
The kernels I run aren't real time. Quite. https://liquorix.net/ [liquorix.net] Dude does use a lot of the real time optimazations in his core though. His focus is on throughput, which is great for the desktop user. You don't have to wait for other processes before the desktop responds to your latest command.
Ubuntu is a day late, and a dollar short getting onboard the real time kernel train.
Abortion is the number one killed of children in the United States.
(Score: 2) by JoeMerchant on Thursday February 16, @11:10AM
>Ubuntu is a day late, and a dollar short getting onboard
Some call this: conservative vs bleeding edge.
RedHat is way out in front of Canonical in other areas too... Charging for their software comes to mind first.
Україна досі не є частиною Росії Слава Україні🌻 https://news.stanford.edu/2023/02/17/will-russia-ukraine-war-end
(Score: 3, Insightful) by Snotnose on Thursday February 16, @12:26AM (2 children)
Back in 2000 I was porting Linux to the SH4 for a real time system. Another company (Monta Vista?) was doing the real time part, they already had real time working on other CPUs.
In 2004 I was working on a wireless TV system that used real time Linux on an x86 to get the media from the HDD and/or network (we supported 4 stream), and wirelessly sent to data to a TV on the other side of the building.
I just passed a drug test. My dealer has some explaining to do.
(Score: 1, Informative) by Anonymous Coward on Thursday February 16, @01:53AM (1 child)
In 2004 we ran a Simulink model in realtime on an Opal-RT Linux box. What was about 10x longer than real time (far too slow) in Simulink ran at about 2x faster than realtime once compiled. We used the Matlab Real-Time Workshop compiler and ran under the Opal-RT port of Linux. We needed about 1000 Hz update rate to simulate the physics and the model would run consistently at well over 2000 Hz. And remember this was on a 2004 PC.
https://www.opal-rt.com/ [opal-rt.com] No further connection with the company after 2004, but a very nice experience at the time.
(Score: 0) by Anonymous Coward on Thursday February 16, @08:57AM
Are you confusing realtime with realtime (as in realtime kernel)?
(Score: 2) by sonamchauhan on Thursday February 16, @12:30AM (4 children)
Can the x86 version run a modern desktop? What would the experience be like?
(Score: 4, Touché) by coolgopher on Thursday February 16, @12:42AM
From Canonical? Probably Crysis-like.
(Score: 5, Informative) by Rich on Thursday February 16, @02:38AM (2 children)
Yes, it can, and you won't notice a difference to the stock kernel.
Remember that "real-time" does not mean "fast", but "guaranteed deadline". For processes/threads with realtime priority, the kernel will make sure that they are given a guaranteed amount of time slices within a certain timeframe, or react to certain events with guaranteed latency. The Linux kernel is a big pile of stuff with many heuristics to make data center throughput fast. It's more or less the antithesis to realtime, which is why early RT attempts put another kernel below Linux and just ran the whole Linux system as a process that might or might not complete something within the scheduled time for it. These days, even a stock kernel has very low reaction times anyway and really the only "customers" for that would be people like the CNC folks who want to drive steppers at a stable 2kHz or so - which, on x86, isn't even guaranteed with an RT kernel, because the particular BIOS/UEFI might have installed some Ring -1 SMM shit behind your back that breaks your timing with invisible hand.
(Score: 2) by sonamchauhan on Thursday February 16, @03:46AM
Thank you!
(Score: 2) by Reziac on Thursday February 16, @04:26AM
I had the same question. Thank you for your excellent explanation, so I don't have to ask for one in small words. :)
And there is no Alkibiades to come back and save us from ourselves.
(Score: 2) by turgid on Sunday February 19, @02:21PM
Presumably this is still soft realtime (as opposed to hard realtime like you'd get from a proper RTOS like RTEMS, QNX, VxWorks, FreeRTOS etc?
I've used RedHawk Linux before for a soft realtime application. It's a commercial build of RedHat with extensive realtime kernel patches. It still went out to lunch on occasion.
If you need to do hard realtime, don't use Linux.
I refuse to engage in a battle of wits with an unarmed opponent [wikipedia.org].