Eventual Consistency and Transactions Working Together | Hacker News Reader

Eventual Consistency and Transactions Working Together

forum.treode.com

Reminds me of Spanner with some changes.

http://static.googleusercontent.com/media/research.google.co...

TreodeDB a bit like Spanner, in as much as both offer transactions across datacenters. The implementations are very different. The way Treode uses Lamport clocks lets you use a simple rule to determine if your local cache satisfies application invariants. I'm not sure if Spanner's use of atomic clocks gets you a similar capability.

Are there any other databases that can do what you're describing here?

Not that I'm aware of.

CockroachDB and FoundationDB provide scalable and reliable transactions. But they don't offer this interface.

Couchbase has conditional writes, but not batch writes.

I think TreodeDB is the first to bring these things together this way.

HyperDex provides scalable and high-performance transactions. While it is strongly (not eventually) consistent, the underlying technique we use to achieve atomicity of transactions is reminiscent of this approach.

On a related note, our experience is that a tightly implemented database can be much faster than a typical eventually consistent database. It would be great to see performance comparisons from TreodeDB.

That's cool. Indeed, it does look like one could use HypderDex's transactions and cond_put to make something close the batch write described in this post.

However, I don't see the part about Lamport clocks in HyperDex's API. Maybe one could implement that in a layer on top. The technique in the post allows a client to know if the values in its cache satisfy application invariants, even invariants that relate multiple rows. The Lamport clocks are key to making that part work.

I would very much like to provide performance numbers, and Jepsen results, and more for TreodeDB. Along that line though, I'm looking for contributors (or even a co-founder). I've gotten it this far on my own, but I really need help.

Reply on news.ycombinator.com