US 6,725,348 B1 · Data storage device and method for reducing write misses by completing transfer to a dual-port cache before initiating a disk write of the data from the cache

Abstract

A data storage device and method for improving the performance of data storage devices examines a command queue and performs data transfers to memory within the device before prior commands have completed. A process running in the idle loop of the controller in the storage device checks the queue for write requests and if a cache space within a dual-port cache to hold the transfer data is available, the data transfer portion of the transfer is completed, while the device is still waiting for completion of prior commands in the queue, and data transfers are completing from the cache to the physical media for the prior command.

Claims16

Dependent claims

A method for performing write commands in a storage device having storage media, while a first command is pending, comprising the steps of:

first determining that a command queue of said storage device contains a write command;
second determining that a cache space within a dual-port cache is available to contain data for said write command;
responsive to said first and second determining step, first setting up a first DMA transfer for transferring said data for said write command from an interface to said cache space;
and
responsive to completion of said first command, second setting up a second DMA transfer for writing data to said storage media from said cache space.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application

09/418,047Filed 13 Oct 1999

Granted

20 Apr 2004

Term ends

Not estimatedThe source records don’t support an estimate.

Classification5 codes

G06F 3/0613
Improving I/O performance: in relation to throughput
G06F 3/0659
Vertical data movement, i.e. input-output transfer; data movement between one or more hosts and one or more storage devices: command handling…
G06F 3/0674
Single storage device: disk device
G06F 12/0862
Addressing of a memory level in which the access to the desired data or data block requires associative addressing means, e.g. caches: with prefetch

Data storage device and method for reducing write misses by completing transfer to a dual-port cache before initiating a disk write of the data from the cache

Life of this patent

Data storage device and method for reducing write misses by completing transfer to a dual-port cache before initiating a disk write of the data from the cache

Life of this patent

Abstract

Claims16