[TUHS] ATC/OSDI'21 joint keynote: It's Time for Operating Systems to Rediscover Hardware (Timothy Roscoe)

[David Arnold]

> On 17 Sep 2021, at 05:41, Larry McVoy <lm at mcvoy.com> wrote:

<…>

> I think it is that the newer kids are less willing to understand stuff.
> So they build something on top that they understand.  I agree that they
> will hit problems and likely build "safe deposit boxes" because the
> containers are "too complex”.

Writing a new OS in the 70s or even early 80s meant that you had to replace or port a compiler toolchain, an editor, an email client, a news reader, an IRC client, a couple of simple games, and whatever applications your university/research lab needed to justify its grant money.  It was a chunk of work, but it was surmountable by a small team or even a dedicated individual.  It was demonstrably possible to build your own machine from CPU upward within a reasonable timeframe (eg. Wirth’s Oberon).

It’s still possible (and perhaps even easier) to do that today, but no-one’s really happy with an OS that only provides a handful of applications.  In particular, as has been widely stated, a modern web browser is orders of magnitude more work than an OS.  But expectations for every type of application have moved on, and a modern editor, chat/messaging app, or game is also likely orders of magnitude more complex and feature-rich than what was once acceptable.

For a while, it was possible to have a “POSIX emulation” module/layer/whatever (was Mach the first to go this route?) as a shortcut to this but the breadth of the APIs needed to run, eg. Chrome/ium is again orders of magnitude more work than what was needed to port vi/emacs/rn/etc.

And it’s not just those applications: to have your new OS be useful, you need to support a dozen languages, a hundred protocols, thousands of libraries … a vast range of stuff that would take years, perhaps decades, to port over or reinvent in your new paradigm.

The idea that you’d turn your back on the accumulated value of 50 years of countless people’s work because your set of system calls is slightly better than the one you’ve got now … that’s a very, very big call.

So I think the notion that “the kids” are less willing to understand, or to drill deep, is doing them a disservice.  They do understand, and they (mostly) make the choice to leverage that body of work rather than embark on the futility of starting afresh.





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