To clarify, FoundationDB has some documented multi-region features, but it's not at all clear that anybody who runs it at scale relies on those multi-region features [1]. Even if they do, it's not obvious they run this Fearless DR mode at any appreciable latency.
Geo-replication is an area where Anna really shines, and foundation pays severe costs. All of the concurrency control problems have contention footprints on the order of round-trips. Fully optimistic concurrency control needs to expose backoffs quite a few round-trips to be live. Even pessimistic concurrency control requires some number of round trips, probably at least 1.5 optimally, but in practice in most tuned systems, probably 3. A heck of a lot of use cases make sense at 0 global RTTs and don't at 1+. The ability to tell the database how to manage concurrency, and then providing causal is ultimately the best you can do. That's awesome.
At the end of the day, I have to believe that there's a whole big mess of applications we'll build this, on systems in the portion of the design space Anna is choosing, one day. This is only recently not cutting edge research, but it's definitely still research. We don't know how to model these concepts at a high-level and in a composable way where the masses of software developers can engage with them.
It's interesting to think about how long ago we were graced with BAYOU [2], that thing was ahead of its time. I suspect it's going to take a little while longer before these sorts of techniques make their way into data storage primitives we think of as part of the standard vernacular, but I believe we'll get there eventually.
Geo-replication is an area where Anna really shines, and foundation pays severe costs. All of the concurrency control problems have contention footprints on the order of round-trips. Fully optimistic concurrency control needs to expose backoffs quite a few round-trips to be live. Even pessimistic concurrency control requires some number of round trips, probably at least 1.5 optimally, but in practice in most tuned systems, probably 3. A heck of a lot of use cases make sense at 0 global RTTs and don't at 1+. The ability to tell the database how to manage concurrency, and then providing causal is ultimately the best you can do. That's awesome.
At the end of the day, I have to believe that there's a whole big mess of applications we'll build this, on systems in the portion of the design space Anna is choosing, one day. This is only recently not cutting edge research, but it's definitely still research. We don't know how to model these concepts at a high-level and in a composable way where the masses of software developers can engage with them.
It's interesting to think about how long ago we were graced with BAYOU [2], that thing was ahead of its time. I suspect it's going to take a little while longer before these sorts of techniques make their way into data storage primitives we think of as part of the standard vernacular, but I believe we'll get there eventually.
Databases are fun!
[1] https://github.com/apple/foundationdb/wiki/Multi-Region-Repl... A parallel line of reach in this area of the design space out of the EU was https://www.antidotedb.eu/. [2] https://people.eecs.berkeley.edu/~brewer/cs262b/update-confl...