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  | 
               
