A Note About Streaming - HP BB118BV - StorageWorks Data Protector Express Package Addendum

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If this retention policy is over-cautious for your needs, simply select Custom as the
Rotation type to make the GFS-30 model editable. You can then change the number of
sets and edit the write mode, if required, by clicking on the appropriate interval button.
Rotation types are described in more detail in the User Guide.

A Note About Streaming

A stream is a set of files to be backed up asynchronously to other streams. Data Protector
Express automatically enables multi-streaming within the software, providing up to eight
concurrent data streams per drive (depending on license of the edition) and streaming to
multiple devices in parallel.
Streams are assigned to a device in a round robin method. If you have two streams and
two devices, Data Protector Express will use both devices in parallel. Data Protector
Express uses self-tuning logic to determine the most appropriate way of streaming data.
For example, if you are backing up a C: and a D: drive that are both on the same physical
disk, a single stream may be more appropriate to prevent disk thrashing. If the volumes
are on separate disks, two streams can be used.
There is no load balancing logic in place to intelligently assign streams based on their
data size, but any zero-byte streams will be grouped with other streams to avoid using
media unnecessarily.
Backups and Rotation Types