Batching is a pattern I’ve had to manually build in the past to push large amounts of analytic data to a database. I’d push individual events to be logged, map reduce those in batches and then perform insert on duplicate update queries on the database, otherwise the threshold of incoming events was enough to saturate the connection pool making the app inoperable.

Even optimizing to where if an app instance new it ran the inert on update for a specific unique index by storing that in a hash map and only running updates from there on out to increase the count of occurrences of that event was enough to find significant performance gains as well.