Retention

Events are kept in Redis for 24 hours by default. Every stream on a model reads the same events, so they're removed by age, and not when they're consumed.

const DAY = 24 * 60 * 60 * 1000

const live = new ZenStackLive({
  client,
  retention: 3 * DAY,

  redis: {
    url: process.env.REDIS_URL!,
  },
})

retention is how long a stream can be offline and still catch up. Anything older is gone: a stream that's offline for longer misses what it didn't read, and events waiting to be retried are dropped. The cost of a longer retention is memory, which depends on how much your captured tables change, whether or not anyone is reading.

retention is set per ZenStackLive, and can't be set per stream. If several services read the same table with different values, the shortest one takes effect while that service is running, so give them all the same value.

How Trimming WorksCopy Anchor Link

Old events are removed once a minute in two places:

• Each running stream trims its own table, using its retention.
• Each ZenStackLive trims every published table in the background. It keeps events for the longest retention recorded for that table, or its own if there are none, so it covers tables whose streams aren't running.

So you never need to do anything to keep Redis from growing. What a deleted stream leaves behind can't outgrow retention.

The exception is when you remove LIVE altogether. With no instance running, nothing trims, and Debezium keeps writing. Run prune first.