E-RAID system and method of operating the same

• US 20020069317A1
• Filed: 11/30/2001
• Published: 06/06/2002
• Est. Priority Date: 12/01/2000
• Status: Abandoned Application

• Current Assignee: James R. Hsia, Yan Chiew Chow
• Original Assignee: James R. Hsia, Yan Chiew Chow
• Inventors: Hsia, James R., Chow, Yan Chiew
• Application Number:
  US10/007,410
• Publication Number:
  US 20020069317A1
• Time in Patent Office: Days
• US Class Current: 711/104
• CPC Class Codes: G06F 11/108 Parity data distribution in semiconductor storages, e.g. in SSD
• CPC Class Codes: G06F 11/1441 Resetting or repowering
• CPC Class Codes: G06F 11/1666 where the redundant component is memory or memory area
• CPC Class Codes: G06F 11/20 using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements
• CPC Class Codes: G06F 11/201 between storage system components
• CPC Class Codes: G06F 12/0802 Addressing of a memory level in which the access to the desired data or data block requires associative addressing means, e.g. caches
• CPC Class Codes: G06F 12/0868 Data transfer between cache memory and other subsystems, e.g. storage devices or host systems
• CPC Class Codes: G06F 12/0873 Mapping of cache memory to specific storage devices or parts thereof
• CPC Class Codes: G06F 2212/214 Solid state disk
• CPC Class Codes: G06F 2212/262 configured as RAID
• CPC Class Codes: G06F 2212/263 Network storage, e.g. SAN or NAS
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0626 Reducing size or complexity of storage systems
• CPC Class Codes: G06F 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing

Abstract

An apparatus and method for storing, manipulating, processing, and transferring data in a memory subsystem (110) to provide a dynamic-RAID system Generally, the memory subsystem (110) includes a memory array (255) having number of memory devices (250) arranged in banks (260) each with a predetermined number of devices, a memory controller (265) coupled to the banks for accessing the devices, and a processor (275) coupled to the controller and through a network (120) to a data processing system (115). The memory controller (265) is configured to store data to any combination of banks (260) in one or more memory matrix modules (105) simultaneously to provide a dynamic-RAID system. Preferably, the controller (265) is configured to detect and correct errors in data transferred to or stored in the memory devices (250) using a Hamming code.

Claims

1. A memory system having a matrix unit comprising:

a plurality of memory devices each capable of storing data therein, the memory devices arranged in a plurality of banks each having a predetermined number of memory devices; and

a memory controller coupled to the banks for accessing the memory devices, the memory controller configured to store data simultaneously in any combination of the banks to provide an e-RAID system.

2. A memory system according to claim 1, wherein the memory controller is configured to store blocks of data, in regular sequence, to all of the banks of memory devices to provide an e-RAID Level 0 system.

3. A memory system according to claim 1, wherein the memory controller is configured to mirror the data stored in a first group of half of the banks to a second group of another half of the banks to provide an e-RAID Level 1 system.

4. A memory system according to claim 1, wherein the memory controller is configured to mirror the data stored in a first group of half of the banks, the first group configured as an e-RAID Level 0 system, into a second group of another half of the banks, the second group also configured as an e-RAID Level 0 system, to provide an e-RAID Level 0+1 system.

5. A memory system according to claim 1, wherein the memory controller is configured to store data to a first group of half of the banks, the first group configured as an e-RAID Level 0 system, generating the Hamming code ECC for each data word stored to the first group, and storing the Hamming code ECC to a second group of another half of the banks, the second group also configured as an e-RAID Level 0 system, to provide an e-RAID Level 2 system.

6. A memory system according to claim 1, wherein the memory controller is configured to store data to a first group of the banks, the first group configured as an e-RAID Level 0 system, and storing the parity data for each sequence or stripe of data spanning the first group of banks to a second group of the banks, to provide an e-RAID Level 3 system.

7. A memory system according to claim 1, wherein the memory controller is configured to store data, in regular sequence, to a plurality of equally sized partitions of the banks, each partition configured as an e-RAID Level 3 system, to provide an e-RAID Level 0+3 or Level 53 system.

8. A memory system according to claim 1, wherein the memory controller is configured to store data as entire blocks to multiple independent partitions of a first group of the banks, generating the parity data for same rank blocks, and storing the parity data to a second group of the banks, to provide an e-RAID Level 4 system.

9. A memory system according to claim 1, wherein the memory controller is configured to stripe data across the banks and storing parity data for each stripe of data in at least one of the banks to provide an e-RAID Level 5 system.

10. A memory system according to claim 1, wherein the memory controller is configured to stripe data across the banks, generating parity data for each stripe of data using two independent parity schemes, and storing the two parity data in at least one of the banks to provide an e-RAID Level 6 system.

11. A memory system according to claim 1, wherein the memory controller is configured to store data to a plurality of banks configured as an e-RAID Level 3 system, except that all data reads and writes are cached independently and asynchronously in a memory location external to the banks, and parity data are generated within the cache, to provide an e-RAID Level 7 system.

12. A memory system according to claim 1, wherein the memory controller is configured to use an error checking code to detect and correct errors in data stored in each of the memory devices.

13. A memory system according to claim 1, wherein the error checking code is a Hamming code.

14. A memory system according to claim 1, further comprising a cache coupled to the memory controller, the cache having stored therein one or more copies of a Data Allocation Table (DAT) adapted to describe data stored in the memory devices.

15. A memory system for use in a data network, the memory system comprising at least one memory matrix unit according to claim 1, the memory system further comprising a management unit coupled to the memory matrix unit and to the data network to interface between the memory matrix unit and the data network.

17. A method according to claim 16, wherein the step of writing blocks of data to the banks comprises the step of writing blocks of data, in regular sequence, to all of the banks of memory devices to provide an e-RAID Level 0 system.

18. A method according to claim 16, wherein the step of writing blocks of data to the banks comprises the step of writing the same data to a first group of half of the banks and a second group of another half of the banks to provide an e-RAID Level 1 system.

19. A method according to claim 16 wherein the step of writing blocks of data to the banks comprises the steps of:

writing blocks of data, in a regular sequence, to a first group of half of the banks; and

writing the same data stored in the first group to a second group of half of the banks to provide an e-RAID Level 0+1 system.

20. A method according to claim 16, wherein the step of writing blocks of data to the banks comprises the steps of:

writing blocks of data, in a regular sequence, to a first group of half of the banks;

generating the Hamming code ECC for each data word stored to the first group; and

writing the Hamming code ECC, in a regular sequence, to a second group of half of the banks to provide an e-RAID Level 2 system.

21. A method according to claim 16, wherein the step of writing blocks of data to the banks comprises the steps of:

writing blocks of data, in a regular sequence, to a first group of the banks;

generating the parity data for each sequence or stripe of data spanning the first group of banks; and

writing the parity data, in a regular sequence, to a second group of the banks to provide an e-RAID Level 3 system.

22. A method according to claim 16, wherein the step of writing blocks of data to the banks comprises the steps of:

writing blocks of data, in a regular sequence, to a plurality of equally sized partitions of the banks, each partition configured as an e-RAID Level 3 system, wherein writing data to each partition comprises the steps of

writing blocks of data, in a regular sequence, to a first group of banks in the partition;

generating the parity data for each sequence or stripe of data spanning the first group of banks; and

writing the parity data, in a regular sequence, to a second group of banks in the partition;

to provide an e-RAID Level 0+3 or Level 53 system.

23. A method according to claim 16, wherein the step of writing blocks of data to the banks comprises the steps of:

writing blocks of data to a plurality of independent partitions of a first group of the banks;

generating the parity data for same rank blocks; and

writing the parity data to a second group of the banks to provide an e-RAID Level 4 system.

24. A method according to claim 16, wherein the step of writing blocks of data to the banks comprises the steps of:

writing blocks of data, in regular sequence, to the banks to provide a stripe of data; and

writing parity data for each stripe of data in at least one of the banks to provide an e-RAID Level 5 system.

25. A method according to claim 16, wherein the step of writing blocks of data to the banks comprises the steps of:

writing blocks of data, in regular sequence, to the banks to provide a stripe of data;

generating parity data for each stripe of data using two independent parity schemes; and

writing the two parity data for each stripe of data in at least one of the banks to provide an e-RAID Level 6 system.

26. A method according to claim 16, wherein the step of writing blocks of data to the banks comprises the steps of:

writing blocks of data, in a regular sequence, to a plurality of equally sized partitions of the banks, each partition configured as an e-RAID Level 3 system, wherein writing data to each partition comprises the steps of

writing blocks of data, in a regular sequence, to a first group of banks in the partition;

generating the parity data for each sequence or stripe of data spanning the first group of banks; and

writing the parity data, in a regular sequence, to a second group of banks in the partition by caching all data reads and writes independently and asynchronously in a memory location external to the banks, and

generating parity data within the cache, to provide an e-RAID Level 7 system.

16. A method of storing data in one or more memory matrix units having a plurality of memory devices arranged in a plurality of banks each having a predetermined number of memory devices, the method comprising the step of simultaneously writing blocks of data to a predetermined combination of the banks contained in one or more of the memory matrix units to provide an e-RAID system.