Home > Storage > PowerScale (Isilon) > Industry Solutions and Verticals > Media and Entertainment > PowerScale OneFS: A Metadata Driven Approach to On Demand Tiering > Overview
A OneFS file system can potentially be made of multiple types of storage nodes. These node types can include all flash F-series nodes, hybrid spinning disk plus flash H-nodes, and archive A-nodes. Each node type has its own performance profile based on a combination of storage type and system resources. The nodes cluster together into a single file system and OneFS provides tools to transparently direct or migrate data among storage types. Crucially, when data is migrated between storage pools, the file path remains the same. The data movement is transparent to users and systems accessing the data.
SmartPools is the mechanism within OneFS that gives administrators control over which node pool (nodes of the same type are grouped into “node pools”) data resides on. File Policies are what determine this behavior. File Policies are configured in the OneFS user interface under File System > Storage Pools > File Pool Policies.
File Pool Policies allow administrators to define criteria that determine on which node pool data lands, when it is initially written to the OneFS storage cluster. Other criteria determines when or if that data should migrate between node pools. These criteria are:
These attributes can be combined with conditional arguments to create sophisticated rules. File Policies are hierarchical with higher-level policies taking precedence over lower-level policies.
To reiterate, there are essentially two types of File Policies:
Typically, this second type of policy runs on a schedule, typically once a day.
The techniques outlined in this paper provide storage administrators the power to migrate data between tiers whenever it is necessary, without having to wait for the full SmartPools job to complete. For example, perhaps an uncompressed image sequence used in a cinematic production needs to be moved from archive to flash for a DaVinci Resolve finishing session.