During db downtime I would like to keep data in temporary storage and process it later with certain amount of delay(2mins interval)

Question

Requirement:

Hold the data during db downtime and process it with 5 mins interval by keeping them in dead letter queue.

I have tried below approaches

1. Kafka retry topic but there are some limitations where I have no control over the listener to configure the interval. @kakfkalistner is picking the message as soon as we push

2. Pick the message from Kafka listener and storing it in hashset. Create schedular to scan the hashset in 5mins delay and wipe out(this approach is not handy since set is in memory)