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 ContentDirectors manage and direct the overall operation of the Omneon MediaGrid. They
enable clients to interact with the system by creating and presenting a single virtual file system
constructed from MediaGrid's many individual ContentServer storage devices.
All clients initially contact one of the clustered ContentDirectors for file access requests (e.g.
open, read, write, etc.). The selected ContentDirector responds with a list of target Content-
Servers for the transaction, enabling clients to then connect directly to a set of individual Content-
Servers for data access.
During write operations, ContentDirectors determine the distribution of slices, which are the units
of data stored across multiple ContentServers in a MediaGrid system. ContentDirectors use a
heuristic algorithm weighing dynamic usage factors including ContentServer load and capacity
to allocate slices to individual ContentServers. For subsequent read operations, this distribution
enables the ContentDirector to actively load-balance the available storage and bandwidth of the
system in order to ensure reliable, high-performance operation. With multiple ContentServers
serving an individual client's read/write request, this approach eliminates any bandwidth bottlenecks
commonly found in NAS storage systems that pass content through a single controller.
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