I have a small MariaDB RDS Instance running on AWS. Every once in a while, the instance quickly starts to use the available storage (not the tablespace) and becomes 100% full, i.e. 100% storage full. Then it's locked by AWS, storage optimization happens and all that storage is released. I want to be able to debug this problem, but I don't have a clue why the DB would end up with full storage? Any clues to help me diagnose this? Where should I go look?
Now the Write IOPs suggest that I'm writing a ton of data to the DB. But that's mostly 'select' statements on a DB that's 400 MBs worth of data. ALL the temporary storage used is released after RDS is done with optimization. Is there a fix?