Data path accelerator for storage systems

• US 20020161850A1
• Filed: 01/29/2002
• Published: 10/31/2002
• Est. Priority Date: 01/29/2001
• Status: Abandoned Application

• Current Assignee: Braodband Storage LLC, Snap Appliance, Inc. (Silicon Valley Technology Partners LLC)
• Original Assignee: Adaptec Incorporated (Steel Partners Holdings LP)
• Inventors: Schweitzer, James R., Bolstad, Gregory D., Staub, John R., Randall, Jay G., Ulrich, Thomas R., Priester, Wilbor George
• Application Number:
  US10/060,977
• Publication Number:
  US 20020161850A1
• Time in Patent Office: Days
• US Class Current: 709/214
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 11/2035 without idle spare hardware
• CPC Class Codes: G06F 11/2048 where the redundant components share neither address space nor persistent storage
• CPC Class Codes: G06F 11/2097 maintaining the standby controller/processing unit updated initialisation or re-synchronisation thereof G06F11/1658 and subgroups
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: G06F 9/5083 Techniques for rebalancing the load in a distributed system

Abstract

A data path controller architecture for a file server is described. The system includes a network interface for communicating with one or more clients and a storage interface for communicating with one or more disk drives. The file server further includes a data engine that is configured to communicate with the storage interface to receive file data from the one or more disk drives. The data engine is further configured to communicate with the network interface to send file data to the one or more clients. A CPU is configured to queue transaction requests for the data engine in response to file requests from the one or more clients. The data engine is configured to receive file data in response to at least a portion of the transaction requests. The data engine is further configured to send file data to the one or more clients in response to at least a portion of the transaction requests.

Claims

1. A computer network file system, comprising:

a first file server;

a second file server, said first file server configured to select an infrequently accessed file and push said infrequently accessed files to said second server, thereby improving a balance of unused storage capacity between the first server and the second server without substantially affecting a loading for each of the first and second servers;

first file system metadata loaded on said first file server; and

second file system metadata loaded on said second file server, said first file system metadata and said second file system metadata configured to allow a client to locate files stored by said first file server and files stored by said second file server without prior knowledge as to which file server stores said files.

2. A computer network file system, comprising:

a first file server;

a second file server, said first file server configured to push a copy of a frequently accessed file to said second file server to improve a balance of loading on each of the first and second file servers;

first file system metadata loaded on said first file server; and

second file system metadata loaded on said second file server, said first file system metadata and said second file system metadata configured to allow a client to locate files stored by said first file server and files stored by said second file server without prior knowledge as to which file server stores said files.

3. The computer network file system of claim 2, wherein said first metadata comprises directory information that describes a directory structure, said directory structure including location information for a first file, said location information comprising a server identifier.

4. The computer network file system of claim 2, wherein files stored by said first file server and files stored by said second file server are located in a hierarchical directory structure having a common root directory, said first metadata comprising directory information that describes directories stored on said first file server, said second metadata comprising directory information that describes directories stored on said second file server, said first directory information comprising location information for finding said second directory information.

5. The computer network file system of claim 2, wherein files stored by said first file server and files stored by said second file server are located in a hierarchical directory structure having a common root directory.

6. The computer network file system of claim 2, wherein said first metadata describes directories stored on said first file server, said second metadata describes directories stored on said second file server, and said first metadata comprises location information for locating said second metadata, said location information comprising a server identifier.

7. The computer network file system of claim 2, wherein said first metadata identifies data blocks and parity blocks corresponding to said data blocks.

8. The computer network file system of claim 2, wherein said first metadata identifies parity groups, said parity groups comprising a plurality of information blocks, said information blocks comprising one or more data blocks, said information blocks further comprising a parity block, each of said information blocks stored on a different disk drive.

9. The computer network file system of claim 8, wherein a size of a first parity group in a file is not equal to a size of a second parity group in said file.

10. A method for storing data in a computer network, comprising:

loading first file system metadata on a first file server operably connected to a network fabric;

loading second file system metadata on a second file server connected to said network fabric, said first file system metadata and said second file system metadata aggregating files in a directory structure that spans said first server and said second server to allow a client to locate a file without prior knowledge as to which file server stores said file;

selecting an infrequently accessed file on said first server; and

pushing said infrequently accessed files to said second server.

11. A method for storing data in a computer network, comprising:

loading first file system metadata on a first file server operably connected to a network fabric;

loading second file system metadata on a second file server connected to said network fabric, said first file system metadata and said second file system metadata aggregating files in a directory structure that spans said first server and said second server to allow a client to locate a file without prior knowledge as to which file server stores said file;

selecting a frequently accessed file on said first server; and

pushing said frequently accessed files to said second server.

12. The method of claim 11, wherein said first metadata comprises information to specify a selected logical disk block of a selected file and information to specify a disk that contains said selected logical block.

13. The method of claim 11, wherein said first metadata identifies locations of data blocks and locations of parity blocks corresponding to said data blocks.

14. A computer network file system, comprising:

a first file server;

a second file server;

a file system that aggregates files in a manner that allows a client to locate a file without prior knowledge as to which file server stores said file; and

means for pushing an infrequently-accessed file on said first file server to said second file server.

15. A computer network file system, comprising:

a first file server;

a second file server;

a file system that aggregates files in a manner that allows a client to locate a file without prior knowledge as to which file server stores said file; and

means for pushing a frequently-accessed file on said first file server to said second file server.

16. A computer network file system, comprising:

a first file server;

a second file server;

a file system that aggregates files in a manner that allows a client to locate a file without prior knowledge as to which file server stores said file; and

means for collecting and analyzing a load balance between said first file server and said second file server;

means for moving files between said first file server and said second file server to improve said load balance between said first file server and said second file server.