We built a distributed DB capable of running across 100s of global locations

Re:We built a distributed DB capable of running across 100s ... by zzzcpan on Tuesday March 05, 2019 @07:55AM (#19310186)

So, does it actually have CRDT operations? Doesn't seem like any of the interfaces expose them. Can you use a convergent counter, for example?

Also product page [1] has some weird claims. There is no such thing as "Strong Session Consistency", this is just another name for weak consistency guarantees. And Strong Eventual Consistency, which is a thing, requires using mergeable conflict-free operations that you don't seem to expose? The "smart operation ordering using intent prioritization" is also neither strong eventual consistency nor strong consistency.

[1] https://www.macrometa.co/product

[ Parent | on HN ]

Re:We built a distributed DB capable of running across 100s ... by durga_mm on Tuesday March 05, 2019 @03:07PM (#19313757)

Hi zzzcpan - Yes. The global edge fabric internally uses CRDT operations. It is a conscious choice to not expose the CRDT data types. The idea being the developer work with APIs & Query layer as they do with other databases and underneath the system take care of translating to necessary CRDT operations. Convergent counter is in the works and will be available shortly.

The system has strong consistency within a region (aka datacenter) and strong eventual consistency across data centers. Answering your question, yes we do converge (merge) the changes across regions using conflict-free operations.

Intent prioritization rules comes into picture only when it is impossible for the system to determine the intent of the developer when two conflicting changes occur across regions.

I hope the above helps.

Regards

[ Parent | on HN ]