US5787463A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Disk array system including a dual-ported staging memory and concurrent redundancy calculation capability
Assignee: EMC Corp
•
Filing: 1997-04-15
•
Granted: 1998-07-28
•
Expires: 2017-04-15
Abstract
Abstract The present invention is directed to memory subsystems that use redundant arrays of inexpensive disks (RAID). The subsystem enables dual concurrent accesses to the subsystem buffer by the host and RAID engine, which calculates parity information associated with data being transferred between the host and disk drives, by including a dual-ported staging memory where the host and disk drives are coupled to one port and the RAID engine to the other port. Positioning the RAID engine on the opposite side of the staging memory in relation to the host and disk drives allows for pipelined asynchronous memory subsystem operation, improving system throughput.
Inventors
- 👤 Kumar Gajjar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:24
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/06; G06F3/0601; G06F3/0602; G06F3/061; G06F3/0613; G06F11/00; G06F11/07; G06F11/08; G06F11/10; G06F11/1076; G06F3/0628; G06F3/0629; G06F3/0635; G06F3/0668; G06F3/0671; G06F3/0683; G06F3/0689
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
149 words
In a computer system having a host computer, a storage subsystem and a plurality of storage devices, wherein the host computer transfers data blocks to and from the plurality of storage devices through the storage subsystem, the storage subsystem comprising: a dual-ported memory device for storing the data blocks being transferred between the host computer and the plurality of storage devices, the dual-ported memory device having a first port coupled to the host computer and the plurality of storage devices; and a RAID engine providing pipelined operation of the computer system coupled to a second port of the dual-ported memory device for retrieving a first data block from the dual-ported memory device, calculating parity information associated with the first data block at the same time that a second data block is being transferred to the dual-ported memory device and storing the calculated parity information in the dual-ported memory device.
Claim 2
Dependent Claim
149 words
In a computer system having a host computer, a storage subsystem and a plurality of storage devices, wherein the host computer transfers data blocks to and from the plurality of storage devices through the storage subsystem, the storage subsystem comprising: a dual-ported memory device for storing the data blocks being transferred between the host computer and the plurality of storage devices, the dual-ported memory device having a first port coupled to the host computer and the plurality of storage devices; and a RAID engine providing pipelined operation of the computer system coupled to a second port of the dual-ported memory device for retrieving a first data block from the dual-ported memory device, calculating parity information associated with the first data block at the same time that a second data block is being transferred to the dual-ported memory device and storing the calculated parity information in the dual-ported memory device.
Claim 3
Dependent Claim
40 words
The computer system of claim 1 wherein the RAID engine further comprises a microprocessor for controlling retrieval of data from the dual-ported memory device and calculation of the parity information associated with the retrieved data from the dual-ported memory device.
Claim 4
Dependent Claim
37 words
The computer system of claim 2 wherein the RAID engine further comprises a cyclic redundancy checksum (CRC) logic block coupled to the microprocessor for calculating CRC information associated with the retrieved data from the dual-ported memory device.
Claim 5
Dependent Claim
20 words
The computer system of claim 1 wherein the dual-ported memory device further comprises a video random access memory (VRAM) device.
Claim 6
Dependent Claim
147 words
A computer system comprising: a host computer; a system bus coupled to the host computer for transferring data blocks to and from the host computer; a plurality of storage devices coupled to the system bus for storing the data blocks from the host computer; a dual-ported memory device for storing the data blocks being transferred between the host computer and the plurality of storage devices, the dual-ported memory device having a first port coupled to the system bus; and a RAID engine providing pipelined operation of the computer system coupled to a second port of the dual-ported memory device for retrieving a first data block from the dual-ported memory device, calculating parity information associated with the first data block at the same time that a second data block is being transferred to the dual-ported memory device and storing the calculated parity information in the dual-ported memory device.
Claim 7
Dependent Claim
147 words
A computer system comprising: a host computer; a system bus coupled to the host computer for transferring data blocks to and from the host computer; a plurality of storage devices coupled to the system bus for storing the data blocks from the host computer; a dual-ported memory device for storing the data blocks being transferred between the host computer and the plurality of storage devices, the dual-ported memory device having a first port coupled to the system bus; and a RAID engine providing pipelined operation of the computer system coupled to a second port of the dual-ported memory device for retrieving a first data block from the dual-ported memory device, calculating parity information associated with the first data block at the same time that a second data block is being transferred to the dual-ported memory device and storing the calculated parity information in the dual-ported memory device.
Claim 8
Dependent Claim
32 words
The computer system of claim 5 further comprising: a bus bridge having a first port coupled to the system bus; a memory bus coupled to a second port of the bus bridge.
Claim 9
Dependent Claim
20 words
The computer system of claim 5 wherein the dual-ported memory device further comprises a video random access memory (VRAM) device.
Claim 10
Dependent Claim
40 words
The computer system of claim 5 wherein the RAID engine further comprises a microprocessor for controlling retrieval of data from the dual-ported memory device and calculation of the parity information associated with the retrieved data from the dual-ported memory device.
Claim 11
Dependent Claim
37 words
The computer system of claim 8 wherein the RAID engine further comprises a cyclic redundancy checksum (CRC) logic block coupled to the microprocessor for calculating CRC information associated with the retrieved data from the dual-ported memory device.
Claim 12
Dependent Claim
221 words
In a computer system having a host computer, a storage subsystem and a plurality of storage devices, a method of pipelined system operation for transferring data between the host computer and the plurality of storage devices through the storage subsystem, the method comprising the steps of: providing a dual-ported memory device in the storage subsystem; providing a RAID engine in the storage subsystem; storing a first block of data from the host computer in the dual-ported memory device, wherein the host computer is coupled to a first port of the dual-ported memory device; retrieving the first block of data from the dual-ported memory device to the RAID engine, wherein the RAID engine is coupled to a second port of the dual-ported memory device; processing the first block of data in the RAID engine; storing a second block of data from the host computer to the dual-ported memory device at the same time the RAID engine is processing the first block of data; storing processed information associated with the first block of data from the RAID engine to the dual-ported memory device; and storing the first block of data and the associated processed information from the dual-ported memory device to the plurality of storage devices, wherein the plurality of storage devices are coupled to the first port of the dual-ported memory device.
Claim 13
Dependent Claim
221 words
In a computer system having a host computer, a storage subsystem and a plurality of storage devices, a method of pipelined system operation for transferring data between the host computer and the plurality of storage devices through the storage subsystem, the method comprising the steps of: providing a dual-ported memory device in the storage subsystem; providing a RAID engine in the storage subsystem; storing a first block of data from the host computer in the dual-ported memory device, wherein the host computer is coupled to a first port of the dual-ported memory device; retrieving the first block of data from the dual-ported memory device to the RAID engine, wherein the RAID engine is coupled to a second port of the dual-ported memory device; processing the first block of data in the RAID engine; storing a second block of data from the host computer to the dual-ported memory device at the same time the RAID engine is processing the first block of data; storing processed information associated with the first block of data from the RAID engine to the dual-ported memory device; and storing the first block of data and the associated processed information from the dual-ported memory device to the plurality of storage devices, wherein the plurality of storage devices are coupled to the first port of the dual-ported memory device.
Claim 14
Dependent Claim
31 words
The method of claim 10 wherein the step of providing a dual-ported memory device in the storage subsystem further comprises the step of providing a video random access memory (VRAM) device.
Claim 15
Dependent Claim
38 words
The method of claim 10 wherein the step of processing the first block of data in the RAID engine further comprises the step of calculating parity information associated with the first block of data in the RAID engine.
References Cited (Backward Citations)
EP0156724A1
Cited
EP0201330A2
Cited
EP0266789A2
Cited
US5042014A
Cited
US4870643A
Cited
EP0320107A2
Cited
US5586299A
Cited
US5146574A
Cited
US5349686A
Cited
US5274645A
Cited
US5140592A
Cited
US5166939A
Cited
US5233618A
Cited
US5386548A
Cited
US5185876A
Cited
US5325497A
Cited
US5202856A
Cited
US5226010A
Cited
US5285451A
Cited
US5233692A
Cited
US5134619A
Cited
US5124987A
Cited
US5373512A
Cited
US5471640A
Cited
US5490263A
Cited
US5634033A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-07-27 | 2002-01-26 | 2002-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-07-27 | 2006-01-26 | 2006-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-07-27 | 2010-01-26 | 2010-07-28 | $7700.00 | Window Closed / Lapsed |