Method and apparatus for offloading network processes in a computer storage system

• US 7,937,474 B2
• Filed: 04/30/2008
• Issued: 05/03/2011
• Est. Priority Date: 04/30/2007
• Status: Active Grant

• Current Assignee: NetApp, Inc.
• Original Assignee: NetApp, Inc.
• Inventors: Sanzi, Richard N. Jr., Graham, David, Hicks, Tom, Reynolds, Andrew G., Kazar, Michael L., Gohh, Fred, Nydick, Daniel S.
• Primary Examiner(s): Maung; Zarni
• Application Number:
  US12/112,522
• Publication Number:
  US 20080320142A1
• Time in Patent Office: 1,098 Days
• Field of Search: 709225-229, 709203-205, 709/250, 709220-221
• US Class Current: 709/226
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols

Abstract

A system and method for offloading network processes from main processors of a storage system and performing them on parallel processing modules. Embodiments of the present invention improve performance of a clustered storage system by performing certain network processes in an accelerator module of a storage system node. The accelerator module receives multi-protocol protocol data units (PDUs) from a network interface, performs protocol operations on the PDUs to form file system requests and passes the file system requests to a local D-module. If a file system request is directed to a non-local D-module in the cluster, the accelerator module repackages the request for transmission to the appropriate D-module and passes it back to the network without using local D-module processing resources or passing data over the system bus.

Claims

1. A computer storage system, comprising:

at least one storage system node comprising a local system bus, a local accelerator module connected to the local system bus and configured to perform one or more network operations, and a local storage device element module connected to the local system bus and configured to perform local storage device access operations received through the local system bus; and

the local accelerator module further configured to receive a multi-protocol protocol data unit (PDU), wherein the PDU comprises a storage operating system request directed to a non-local clustered storage device element module, the local accelerator module further configured to transform the storage operating system request into a storage operating system call, and the local accelerator module further configured to perform a network operation to direct the storage operating system call to the non-local clustered storage device element module without using the local system bus.

2. The computer storage system according to claim 1 wherein the local accelerator module issues only locally directed storage operating system calls to the local system bus.

3. The computer storage system according to claim 1 wherein the local accelerator module further comprises:

a packet and connection processor (PCP) configured to communicate with a network and further configured to receive PDUs from the network;

at least one protocol-specific operation parser (OP) module configured to communicate with the PCP and further configured to establish one or more stream connections for the PDU, and further configured to provide instructions and data pointers to at least one protocol-specific protocol handler module;

the at least one protocol handler module configured to communicate with the OP module and further configured to receive the instructions and data pointers from the OP module, the at least one protocol handler further configured to form a request to a cluster interface (CF) module;

the CF module configured to communicate with the at least one protocol handler and further configured to pass the request to a stream transport (ST) module; and

the ST module configured to communicate with the at least one protocol handler, the ST module further configured to transform the PDU into the storage operating system call.

4. The computer storage system according to claim 3 wherein the ST module is further configured to identify a destination storage device element module for the storage operating system call and further configured to forward the storage operating system call to the destination storage device element module without using local storage device element module processes for non-locally directed storage operating system calls.

5. The computer storage system according to claim 3 wherein the local accelerator module further comprises:

a host interface (HostIF) module configured to communicate with the ST module, the HostIF module further configured to receive a locally directed storage operating system call from the ST module and further configured to communicate the locally directed storage operating system call to the local storage device element module.

6. The computer storage system according to claim 3 wherein the local accelerator module further comprises:

a quota manager configured to communicate with the at least one protocol-specific OP module, the quota manager further configured to determine whether a resource request from the at least one protocol-specific OP module can be satisfied with currently available resources; and

a resource allocation module configured to communicate with the at least one protocol-specific OP module, the resource allocation module further configured to allocate requested resources to the at least one protocol-specific OP module.

7. The computer storage system according to claim 1 wherein the storage operating system call comprises a file system call.

8. The computer storage system according to claim 1 wherein the local storage device element module comprises a D-blade.

9. The computer storage system according to claim 1 wherein the local storage device access operations are directed toward one or more disks.

10. The computer storage system according to claim 1 wherein the accelerator module comprises dedicated memory resources configured to reduce demands for system memory resources of the at least one storage system node.

11. The computer storage system according to claim 1 wherein the accelerator module is embodied as a kernel in a storage operating system.

12. The computer storage system according to claim 1 wherein the local system bus comprises a peripheral component interface bus.

13. A computer storage system accelerator module configured to connect to a system bus of a clustered storage system node, comprising:

a packet and connection processor (PCP) configured to communicate with a network and further configured to receive multi-protocol protocol data units (PDUs) from the network;

at least one protocol-specific operation parser (OP) module configured to communicate with the PCP, the OP module further configured to provide instructions to at least one protocol-specific protocol handler module;

the at least one protocol-specific protocol handler module configured to communicate with the OP module to receive the provided instructions and further configured to form a request to a cluster interface (CF) module;

the CF module configured to communicate with the at least one protocol-specific protocol handler and further configured to pass the request to a stream transport (ST) module; and

the ST module configured to communicate with the at least one protocol-specific protocol handler, the ST module further configured to transform the PDU into a storage operating system call, the ST module further configured to identify a destination storage device element module for the storage operating system call without accessing the system bus of the clustered storage system node.

14. The computer storage system accelerator module according to claim 13 wherein the ST module is further configured to forward the storage operating system call to the destination storage device element module without writing non-locally directed storage operating system calls to the system bus.

15. The computer storage system according to claim 14 wherein the storage operating system call comprises a file system call.

16. The computer storage system according to claim 14 wherein the destination storage device element module comprises a D-blade.

17. The computer storage system according to claim 14 wherein the storage system node comprises a network element device module separate from a storage device element module.

18. The computer storage system according to claim 14 wherein the accelerator module comprises dedicated memory resources configured to reduce demands for system memory resources of the clustered storage system node.

19. The computer storage system according to claim 14 wherein the accelerator module is embodied as a kernel in a storage operating system.

20. The computer storage system according to claim 14 wherein the local system bus comprises a peripheral component interface bus.

21. The computer storage system accelerator module according to claim 13 wherein the accelerator module further comprises:

a host interface (HostIF) module configured to communicate with the ST module, the HostIF module further configured to receive a locally directed storage operating system call from the ST module and further configured to communicate the locally directed storage operating system call to a local storage device element module.

22. The computer storage system accelerator module according to claim 13 wherein the accelerator module further comprises:

a quota manager configured to communicate with the at least one protocol-specific OP module, the quota manager further configured to determine whether a resource request from the at least one protocol-specific OP module can be satisfied with currently available resources; and

a resource allocation module configured to communicate with the at least one protocol-specific OP module, the resource allocation module further configured to allocate requested resources to the at least one protocol-specific OP module.

23. The computer storage system accelerator module according to claim 13 configured as a hardware module connected to a network side of the system bus in the node of the storage system cluster, wherein communications from the hardware module to a local storage device element module traverses the system bus.

24. The computer storage system accelerator module according to claim 23, wherein communications from the hardware module to a non-local storage device element module do not traverse the system bus.

25. A method for accelerating computer storage system operations by a clustered computer storage system, comprising:

receiving at least one protocol data unit (PDU) from a network by an accelerator module connected to a system bus of a node in the clustered computer storage system;

parsing each of the at least one PDUs to form a storage operating system request by the accelerator module;

determining by the accelerator module whether the storage operating system request is directed to a local storage device element module on the node or to a remote node of the clustered computer storage system, wherein the determination is made without the accelerator module accessing the system bus; and

communicating non-locally directed storage operating system requests, by the accelerator module, to a non-local storage device element module of the target remote node without accessing the system bus.

26. The method according to claim 25 wherein the accelerator module does not interact with the local storage device element module when the storage operating system request is directed to the non-local storage device element module of the target remote node.

27. The method according to claim 25, further comprising:

determining a protocol of the at least one PDU; and

communicating each of the at least one PDUs to an appropriate protocol handler of the node, wherein the parsing is performed by the appropriate protocol handler.

28. The method according to claim 25 further comprising:

communicating only locally directed storage operating system requests to the local storage device element module via the system bus on the node.

29. The method according to claim 25 wherein the storage operating system call comprises a file system call.

30. The method according to claim 25 wherein the local storage device element module comprises a D-blade.

31. The method according to claim 25 further comprising reducing demands for system memory resources of the node using dedicated memory resources of the accelerator module.

32. The method according to claim 25 further comprising embodying the accelerator module as a kernel in a storage operating system.

33. The method according to claim 25 wherein the node comprises a network element device module operatively connected to the local storage device element module.

34. A non-transitory computer readable storage medium stored on a storage device containing executable program instructions executed by a processor, comprising:

program instructions that receive at least one protocol data unit (PDU) from a network by an accelerator module connected to a system bus of a node in a clustered computer storage system;

program instructions that parse each of the at least one PDUs to form a storage operating system request by the accelerator module;

program instructions that determine by the accelerator module whether the storage operating system request is directed to a local storage device element on the node or to a remote node of the clustered computer storage system, wherein the determination is made without the accelerator module accessing the system bus; and

program instructions that communicate non-locally directed storage operating system requests, by the accelerator module, to a non-local storage device element module of the target remote node without accessing the system bus.

35. The non-transitory computer readable storage medium according to claim 34 further comprising:

program instructions that determine a protocol of the PDU; and

program instructions that communicate the PDU to an appropriate protocol handler of the node, wherein the parsing is performed by the appropriate protocol handler.

36. The non-transitory computer readable storage medium according to claim 34 further comprising program instructions that communicate locally directed storage operating system requests from the accelerator module to the local storage device element module on the node.

37. A computer storage system accelerator module, comprising:

means for receiving at least one protocol data unit (PDU) from a network by an accelerator module connected to a system bus of a node in a clustered computer storage system;

means for parsing each of the at least one PDUs to form a storage operating system request by the accelerator module;

means for determining by the accelerator module whether the storage operating system request is directed to a local storage device element module on the node or to a remote node of the clustered computer storage system, wherein the determination is made without the accelerator module accessing the system bus; and

means for communicating non-locally directed storage operating system requests, by the accelerator module, to a non-local storage device element module of the target remote node without accessing the system bus.