[_jal]

In the dark ages, when running an OS in the way you're referring to 'bare metal' was the default, it meant running something without a traditional kernel underneath it.

Not many things are written to do that, of course. Oracle used to offer an installation mode like this. It was generally a gimmick - you pay for a tiny bit of performance with a ton of flexibility. There are probably use cases where it makes sense, but not that many.

[oblio]

Yeah, but it was a super niche term back then. After 2010, at least, bare metal was used a lot more for: "running the OS we need (+ app) directly on a physical server".

This usage has been, in my experience, a lot more widespread.

[skissane]

> Oracle used to offer an installation mode like this

Oracle, and BEA before them, used to offer a JVM which ran on top of a thin custom OS designed only to host the JVM, you could call it a "unikernel". Product was called JRockit Virtual Edition (JRVE), WebLogic Server Virtual Edition (WLS-VE, when used to run WebLogic), earlier BEA called it LiquidVM. The internal name for that thin custom OS was in fact "Bare Metal". Similar in concept to https://github.com/cloudius-systems/osv but completely different implementation

I think one thing which caused a problem for it, is a lot of customers want to deploy various management tools to their VMs (security auditing software, performance monitoring software, etc) and when your VM runs a custom OS that becomes very difficult or impossible. So adopting this product could lead to the pain of having to ask for exceptions to policies requiring those tools and then defending the decision to adopt it against those who use those policies to argue against it. I think this is part of why the product was discontinued.

Nowadays, Oracle offers "bare metal servers" [1] – which are just hypervisor-less servers, same as other cloud vendors do. Or similarly, "Oracle Database Appliance Bare Metal System" [2] – which just means not installing a hypervisor on your Oracle Database Appliance.

So Oracle seems to have a history of using the phrase "bare metal" in both the senses being discussed here.

[1] https://www.oracle.com/cloud/compute/bare-metal.html

[2] https://docs.oracle.com/en/engineered-systems/oracle-databas...

[aetimmes]

Hmm - what's the overlap between your definition of "bare metal" and the current definition of "embedded"?

I will say, this comment section is the first time I'm hearing about "bare-metal" meaning "without an OS", but the above question is genuine curiosity.

[thowawayyy]

Those terms are orthogonal. Embedded typically refers to running on some HW that is not typically thought of as a computer. Embedded SW can run within an OS or on bare metal.