At a low level, there are distinctions like Sparrow being explicitly p2c based (choose two random workers, then use metrics to pick the "best" between them). We don't p2c at all right now; part of our idea is being able to scale-from-zero to serve incoming requests with sleeping Fly Machines, rather than keeping everything online. And, of course, we run whole VMs (/Docker containers), not jobs with fixed definitions running on long-running executors --- but that's just a detail.
My sense of it is that the big distinction though is that you'd run Sparrow alongside a classic scheduler design like Mesos or Borg or Omega. You'd schedule placement-sensitive servers with the Borglike, and handle Lambda-style HTTP request work with the Sparrowlike.
What we're working on instead if whether you can build something sufficiently Borg-like on top of something Sparrow-like, using "Sparrow-style" scheduling as a low-level primitive. This doesn't quite capture what we're doing (the scheduling API we export implicitly handles some constraints, for instance), but is maybe a good way to think about it.
I should have cited this paper! Thanks for linking it.
Sounds a lot like the Dalton highway , we had to rent a special vehicle which had a radio to do 2 way communication with the traffic and the highway wasn't paved.
A CB radio is not necessary on the Dalton highway, though vehicles that transit it frequently are usually equiped with one to communicate with the semis that make up much of the traffic (especially to coordinate passing on dusty sections). The Dalton has several unpaved sections but is fairly highly maintained and certainly does not require vehicles transiting to perform road work themselves. You certainly do not need survival skills (at least during the summer) to drive it as there is a consistent amount of semi traffic that can assist you if something goes wrong as well as periodic pump stations for the pipline. If anything, the Dalton would be more akin to the Alaska highway some time after it was opened to the public.
It's a combination of pulling and notification. The sqlite DB table is structured like a log, so clients basically just need to keep grabbing the latest id. In practice it's has proven to work pretty well. The code I have public right now does not support HA, I have a private branch that I'm still testing.
[1] https://cs.stanford.edu/~matei/papers/2013/sosp_sparrow.pdf