Distributed I/O store

• US 6,044,367 A
• Filed: 04/15/1998
• Issued: 03/28/2000
• Est. Priority Date: 08/02/1996
• Status: Expired due to Term

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Wolff, James J.
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): Mizrahi, Diane D.
• Application Number:
  US09/060,864
• Time in Patent Office: 713 Days
• Field of Search: 707/1, 707/2, 709/216, 709/223, 709/224, 709/226, 709/239, 709/246, 709/200, 711/202, 714/4, 714/7, 395/200.19, 395/200.32, 364/188, 364/187, 370/399, 345/349
• US Class Current: 707/704
• CPC Class Codes: G06F 16/1767 Concurrency control, e.g. optimistic or pessimistic approaches
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: Y10S 707/915 Image
• CPC Class Codes: Y10S 707/959 Network
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing

Abstract

The current invention provides a method for improving throughput to or from a resource by allowing multiple servers to concurrently access the resource without affecting the integrity of the resource. Generally, by allowing one server to handle the administrative management of a resource, while allowing all servers, including the administrative server, to handle the actual passing of data associated with the I/O request, allows for increased bandwidth between clients and the resource. An I/O request to a first server node is converted into an access portion and a data transfer portion. The access portion is passed to a corresponding administrative server node for the resource. Subsequently, the administrative server may issue an access grant to the first server node. In response, the first server completes the data transfer for the resource.

Claims

1. A method for implementing I/O requests on a network including a plurality of server nodes and at least one resource coupled to at least two of the plurality of server nodes, the method comprising:

receiving at a first of the plurality of server nodes an I/O request for a data set located on the at least one resource;

sending from the first of the plurality of server nodes to a second among the plurality of server nodes an access request for a location of the data set on the at least one resource;

receiving at the second among the plurality of server nodes the access request for the location of the data set on the at least one resource;

verifying at the second among the plurality of server nodes that the requested data set includes access privileges for a node generating the I/O request, wherein the access privileges comprise at least one of a group of access privileges consisting of;

a security privilege indicating the access rights of the node generating the request, a parameter privilege indicating that the parameters of the access request are valid, and a lock privilege indicating whether another I/O request has obtained a lock that conflicts with the request;

identifying, at the second among the plurality of server nodes, the location of the data set on the at least one resource;

sending from the second among the plurality of server nodes to the first among the plurality of server nodes the list, responsive to an affirmative result of the verifying act;

receiving at the first among the plurality of server nodes a list from the second among the plurality of server nodes listing the location of the data set on the at least one resource; and

completing at the first among the plurality of servers a data transfer of the data set at the location on the at least one resource listed in the received list.

24. A computer usable medium having computer readable program code means embodied therein for implementing the method of claim 1.

2. A method for implementing I/O requests, the I/O request includes a write request, on a network including a plurality of server nodes and at least one resource coupled to at least two of the plurality of server nodes, the method comprising:

receiving at a first of the plurality of server nodes on I/O request for a data set located on the at least one resource;

sending from the first of the plurality of server nodes to a second among the plurality of server nodes an access request for a location of the data set on the at least one resource responsive to the receiving act;

receiving at the second among the plurality of server nodes the access request for the location of the data set on the at least one resource;

determining, at the second among the plurality of server nodes, whether the data set is locked;

identifying, at the second among the plurality of server nodes, the location of the data set on the at least one resource;

sending from the second among the plurality of server nodes to the first among the plurality of server nodes the list, when the data set is unlocked;

receiving at the first among the plurality of server nodes a list from the second among the plurality of server nodes listing the location of the data set on the at least one resource responsive to the sending act; and

completing at the first among the plurality of servers a data transfer of the data set at the location on the at least one resource listed in the list received in said receiving act.

3. A method for implementing I/O requests, including a write request, on a network including a plurality of server nodes, and at least one resource coupled to at least two of the plurality of server nodes, the method comprising:

receiving at a first of the plurality of server nodes on I/O request for a data set located on the at least one resource;

sending from the first of the plurality of server nodes to a second among the plurality of server nodes an access request for a location of the data set on the at least one resource responsive to the receiving act;

receiving at the second among the plurality of server nodes the access request for the location of the data set on the at least one resource;

identifying a location of the data set on the at least one resource in response to the receiving act;

determining that the location of the data set does not include sufficient space to fulfill the write request;

allocating free space on the at least one resource sufficient to fulfill the access request;

sending from the second among the plurality of server nodes to the first among the plurality of server nodes the list corresponding both to the location of the data set and the location of the free space allocated in the allocating space;

receiving at the first among the plurality of server nodes a list from the second among the plurality of server nodes listing the location of the data set on the at least one resource responsive to the sending act; and

completing at the first among the plurality of servers a data transfer of the data set at the location on the at least one resource listed in the list received in said receiving act.

4. The method of claim 3, wherein the completing act further comprises the acts of:

initializing out the free space location to a known security pattern before data transfer of the data set.

5. The method of claim 3

wherein identifying a location of the data set further comprises reading a directory database on the at least one resource which contains locations for a plurality of data sets, to determine the location of the data set, and

wherein allocating free space further comprises writing to the directory database an update to the location of the data set to include the free space.

6. The method of claim 3 wherein the data set comprises at least one record in a database.

7. The method of claim 3 wherein the data set comprises at least one file.

8. The method of claim 3 wherein the data set comprises at least one digital image.

9. The method of claim 3 wherein the first I/O request includes one of a group of I/O requests consisting of:

a read request and a write request.

10. The method of claim 3 wherein the I/O request originates at the first server node.

11. The method of claim 3 wherein the I/O request originates at a client node to the plurality of server nodes.

12. A method for implementing I/O on a network including a plurality of server nodes and at least one resource coupled to at least two of the plurality of server nodes, the method comprising:

receiving at a second among the plurality of server nodes an access request from a first among the plurality of server nodes for the location of the data set on the at least one resource;

identifying the location of the data set on the at least one resource in response to the receiving the access request;

verifying that the requested data set includes access privileges for a node generating the I/O request, and the access privileges comprising at least one of a group of access privileges consisting of;

a security privilege indicating the access rights of the node generating the request, a parameter privilege indicating that the parameters of the access request are valid, and a lock privilege indicating whether another I/O request has a lock that conflicts with the request;

sending from the second among the plurality of server nodes to the first among the plurality of server nodes the list, responsive to an affirmative result of verifying that the requested data set includes access privileges for the node generating the I/O request.

13. The method of claim 12

wherein the access request includes a write request,

wherein identifying the location of the data set further comprises determining at the second among the plurality of server nodes whether the data set is locked and identifying the location of the data set on the at least one resource, and

wherein sending the list further comprises sending from the second among the plurality of server nodes to the first among the plurality of server nodes the list, when the data set is unlocked.

14. The method of claim 12

wherein the access request includes a write request,

wherein identifying the location of the data set further comprises determining that the location of the data set does not include sufficient physical space to fulfill the write request and allocating free space on the at least one resource sufficient to fulfill the first I/O request, and

wherein sending the list further comprises sending from the second among the plurality of server nodes to the first among the plurality of server nodes the list corresponding both to the location of the data set and the free space allocated in the allocating act.

15. The method of claim 14 further comprising initializing out the free space location to a known security pattern before data transfer of the data set.

16. The method of claim 14

wherein identifying the location of the data set further comprises reading a directory database on the at least one resource which contains locations for a plurality of data sets, to determine the location of the data set, and

wherein allocating free space further comprises writing to the directory database an update to the location of the data set to include the free space.

17. The method of claim 12 wherein the data set comprises at least one record in a database.

18. The method of claim 12 wherein the data set comprises at least one file.

19. The method of claim 12 wherein the data set comprises at least one digital image.

20. The method of claim 12 wherein the access request is responsive to one of a group of I/O requests consisting of:

a read request and a write request.

21. The method of claim 12 wherein the access request is generated by a first server node among the plurality of server nodes in response to an I/O request.

22. The method of claim 12 wherein the I/O request originates from a client node coupled to the plurality of server nodes.

23. The method of claim 12 wherein the I/O request originates from the first server node.

25. A computer usable medium having computer readable program code means embodied therein for implementing the method of claim 12.