Since server version 2.00.6, DolphinDB introduced a tiered storage strategy, which is only applicable to cluster mode. Tiered storage allows older data to be migrated to slower disks or cloud storage (S3). Old data (cold data) stored locally is infrequently accessed but consumes many resources. With tiered storage, cold data can be stored in the cloud or moved from fast disks (e.g., SSDs) to slower disks (e.g., HDDs), effectively saving resources.

The architecture of tiered storage is:

Hot data storage volumes → cold data storage volumes (coldVolumes) → stale data (deleted)

For more information, please refer to docs:https://ci.dolphindb.cn/en/Tutorials/tiered_storage.html