LAZY_PERSIST memory storage policy

Use the LAZY_PERSIST storage policy to store data blocks on the configured DataNode memory.

For LAZY_PERSIST, the first replica is stored on RAM_DISK (DataNode memory), and the remaining replicas are stored on DISK. The fallback storage for both creation and replication is DISK.

The following table summarizes these replication policies:

Policy ID

Policy Name

Block Placement (for n replicas)

Fallback storage for creation

Fallback storage for replication

15

LAZY_PERSIST

RAM_DISK: 1, DISK:n-1

DISK

DISK