(57) ABSTRACT A storage controller configures a plurality of storage tiers. A Sub-unit of a
storage unit is maintained in a selected Storage tier of the plurality of storage tiers, for at …

A storage tier management application indicates a heat index for each extent of a plurality of
extents, wherein a higher heat index indicates a greater frequency of usage of tracks of an …

(57) ABSTRACT A storage volume functioning at least in part as cache for a tiered storage
system, the storage volume having an in memory write extent consisting of write-accessed …

Storage system comprises a cluster of storage controllers communicatively coupled to a
storage device. Each storage controller is associated with a storage namespace in the …

An approach is provided in which a storage system includes a first storage controller, a
second storage controller, and multiple logical units. The storage system determines that a …

An approach is provided in which a storage system includes a first storage controller, a
second storage controller, and multiple logical units. The storage system detects that a con …

(57) ABSTRACT A method for operating a storage controller reduces a probability of data
loss in a storage system having redundant arrays of independent storage volumes (RAID) by …

A plurality of storage controllers configured to initiate an action based on redundant copies
of metadata, such that a source authority of one of the plurality of storage controllers …

Methods and structure for load balancing ofbackground tasks between storage controllers
are provided. An exemplary active storage controller comprises a front-end interface that …

(57) ABSTRACT A storage controller maintains extent space efficient storage volumes in a
primary allocation space and a secondary allocation space. An indicator is used to indicate …