What happens when RDS freeable memory runs out?
We have a rather large mysql instance on RDS and the freeable memory is starting to get low (<1GB) in the last 24 hours.
What will happen if we reach 0 freeable memory? Does that mean all memory available is used? does that mean the database will crash? Is that a disaster waiting to happen or will that memory simply be recycled?
Solution 1:
Freeable memory is used by db engine for caching. Old data will be removed to get more room.
This is not important as cpu or iops, so you should not worry too much. But, more memory will allow your db engine to respond faster.