Power conservation based on caching
AssigneeWestern Digital Technologies, Inc.
InventorsJOHN E. MARONEY, HAI LE
Life of this patent
Estimating the term…
Abstract
The present invention relates to a method and device that conserves power. In some embodiments, the device is a battery powered storage device. The invention employs a large cache and aggressive caching algorithm to serve data from the storage media (hard disk or SSD) or write data to the storage media. The cache provides an efficient location from which to serve data, especially multi-media. In one embodiment, the algorithm determines when to place the drive into a lower power state, such as idle, or standby, based on the amount of anticipated idle time provided by the large cache.
Claims20
A method of conserving power consumed by a battery powered storage device, wherein said storage device comprises a wireless interface, a storage medium, a memory, and a read cache, said method comprising:
- receiving a request for a file stored on the storage medium;
- determining a block size for servicing the request, wherein a first block size is serviced from the memory and wherein a second block size is serviced from the read cache;
- reading ahead, from the storage medium, at least one block at the second block size for the requested file when the requested file exceeds a threshold size;
- caching, in the read cache, the at least one block of data at the second block size for the requested file;
- and
- modulating power consumption of the storage device for a time period based on the block size determined for servicing the request, a transmission rate of the wireless interface, and a rate of consumption of the requested file.
A dual caching mode battery-powered storage device, said storage device comprising:
- a wireless interface configured to provide a wireless connection to at least one client;
- a memory configured to provide blocks of a requested file;
- a read cache configured to provide larger blocks of a requested file;
- a storage medium;
- and
- a controller configured to cache blocks of a requested file in the memory in a first caching mode, cache larger blocks of a requested file in the read cache in a second caching mode, and control power consumption based on the caching mode, a data rate of the wireless interface, and rate of consumption by the at least one client.
Dependencies are inferred from the claim text.