Not just that but holy shit some of those commercial RTOSes have major issues. I work in aerospace and we recently used one where the whole system would crash after ~230 days of uptime.

At least with Linux you're getting a system that's been used so much that all major issues like that are ironed out. Nothing beats a few million testers.

248 days of uptime by any chance?

edit: I saw the same on a fleet of thousands of JVMs which hung on 100% CPU after 248 days very consistently. Closest thing to an explanation I ever got was perhaps it is storing uptime in hundredths of a second (why not ms???) in signed 32 bit integers, see: https://ma.ttias.be/248-days/ In the end we solved it by restarting with a cronjob between 2am and 4am after 247 days...

One thing to look at is the sum of Anonpages if you have THP enabled. That was enabled by default after CentOS6.2. The usage itself isn't an issue, but there is a known memory leak in THP and the fragmentation can get wedged after a couple hundred days based on usage characteristics of the server.

Million? For linux perhaps billion :)

Ubuntu Linux has millions of testers, your custom version has only been tested by you and your customers :)

Hmm, doubt that there are millions of folks testing Ubuntu controlling a car.

Unless you patch the kernel very heavily, no.

> There aren't many RTOS engineers on the market; there are many Linux engineers.

There aren't many Linux engineers who have experience with resource-constrained systems or real-time programming requirements.

What about people who make video games? There is a great video on YouTube called "Software powering Falcon 9 & Dragon - Simply Explained" which goes more into this topic.

(I don't have any experience with real-time applications.) What are some things they had to do to harden the kernel?

>Same reason SpaceX eschews radiation-hardened processors for redundant off-the-shelf cores

A devil-may-care throw-caution-to-the-wind cavalier attitude?

>supplier competition

I stand corrected. And I'm never buying a Tesla or property even remotely close to SpaceX launch sites...

I would imagine commoditization generally increases - those variables which market values. In this case I presume the variables include reliability since that stuff is probably used in IoT systems where minimizing maintenance can be probably considered am asset.

Although I don't know the market. It might screwed by some weird market dynamic.