What's cooking in RonDB

 Here is a short update on what is going on in the RonDB development. We recently launched the new RonDB release 22.10.2.

We are now working on a number of major improvements and new features.

The first feature we are working on is what we call Pushdown Aggregation. In the first step it will be able to perform Pushdown of aggregation on a single table. This is useful for Hopsworks Feature Store in that it will enable us to store time windows of certain features and compute aggregates as an online feature. This means that data will live in RonDB for a certain time and after that it will be deleted. So a part of this feature will be a Time-To-Live (TTL) feature that will enable users to declare what time window they want the data to visible. The deletion process will be handled by the new C++ REST API Server that will replace the current Go REST API Server. The C++ REST API Server have superior performance to the Go REST Server and will have exactly the same features with a set of new ones added as well.

So Pushdown Aggregation contains five parts, first a new interpreter that calculates the aggregates as part of scan operations. Second new additions to the NDB API to be able to issue those aggregation queries towards the RonDB data nodes. Third a new SQL engine that can execute SQL queries using aggregates on a single table. Fourth, the ability to call this SQL engine through a REST call and finally the TT'L feature to ensure that the rows can automatically disappear when no longer needed by the online data store.

The second feature we are working is a Kubernetes operator for RonDB. This will make it possible to start and stop RonDB clusters in on-prem settings, cloud settings and hybrid cloud settings. In addition it will contain Autoscaling of both MySQL Servers, REST servers and RonDB data nodes. Eventually it will also support global replication between multiple RonDB clusters.

We are also working on a Rate limit and Quota feature that will enable setting limits on both memory and disk usage and the amount of CPU usage a specific database is allowed to use.

So in short a number of very interesting new additions to RonDB that will make it even easier to use RonDB and prosper from the use of it.

There is also some minor features added to support even more pushdown of calculations that makes it possible to push filters based on values of array objects.