What is the oldest x86 processor that is still supported by a modern Linux kernel in present time?
I asked the above quiz question during the Geekcamp tech conference in Nov 2017 during my emcee role. The theoretical answer as you can glean from the title of this post is the 486 which was first released in 1989. I determined that fact from this article where support for the 386 was dropped in Dec 2012.
To get you interested, here is the result of my effort.
The problem here is that along with the vast expansion of computing resources over time, the kernel and user land have both, like a gas, expanded to fill the usable space.
I mean, honestly, “64MB minimum, 1GB suggested”. The “suggested” memory is SIXTEEN TIMES the minimum values? We’re talking night and day here.
Of course, Back In The Day, Linux (and BSD et al) booted “just fine” on our crummy 486 (and 386) machines. Back in The Day, NeXTSTEP booted and ran (reasonably) well in 8MB on at 25Mhz 68040. It certainly ran much better on 20MB of RAM. But this was a full boat graphic environment running PostScript (not know for being “cheap” or frugal).
Of course the old workstations with their simple GUI shells (Suntools, early X) ran with even smaller amounts of memory. Sun 3/50 had, at most, 4MB of RAM. And, no, it was not renowned as a speed demon. But it’s ran Unix just fine.
So, not to reminisce about the “good ol days”, but just to point out that simply having a kernel that will run on the processor is but one aspect of the whole. It’s the entire system that you need to be concerned about.
I imagine if you grabbed a FreeBSD v3 or v4, it would “work just fine” as they were more contemporary of the hardware at the time. I only cite BSD simply because it’s a single, coherent whole of kernel and user land. No doubt you could find a suitable Linux kernel, I just don’t know where you’d find a related user land (outside of downloading old InfoMagic Slackware CD images perhaps).