Although SAP HANA is an in-memory database, it does require a persistent disk to save data which is used less frequently (cold data) by the database. This is non-volatile storage. The SAP HANA database requires persistent storage media to store data and log files during save operations. It also helps to reduce the risk of losing data in case of hardware failure or power cutoff. Every 5 minutes savepoint is triggered in the database which flushes all changed data from memory to data volumes. The persistence layer protects and stores the data in the disk.