Spelunking CACM: Some Thoughts on Operating Systems

Reading through these early papers, it's astounding how much the Titans understood, and what they could see. This is perhaps most evident in the field of operating systems.

I am known for saying, "Hardware has been ahead of software for my entire life," but it's important to make the distinction between vision and implementation in both. Also, for OSes, hardware support is often key, so they develop hand in hand, and given the difficulty of effective simulation, it may be natural for software to lag hardware, but here I am not talking about a few months; I think it takes us YEARS to fully exploit the bounty of computational capabilities that the hardware gods provide. See, for example, Larus's Spending Moore's Dividend.

And obviously, OSes continue to be developed, hopefully on a largely monotonic upward trend.

But here I want to talk about the profound ideas in operating systems. And, despite my general optimism and respect for the younger generations, this is going to sound pessimistic...

I don't think we have had a Truly Important idea since the late 1960s or early 1970s.

By that time, the basic structure was in place: the program and the process; multiprogramming and multitasking; files and hierarchical file systems; virtualization of memory and entire systems; inter-process communication; shared-memory and distributed-memory parallel processing; networks; even the rudiments of distributed file systems and systems existed in Farber's DCS. It was all there.

So...

What was the last "this changes everything" idea in operating systems?