Load balancing method and system using multiple load balancing servers

• US 7,500,243 B2
• Filed: 08/17/2001
• Issued: 03/03/2009
• Est. Priority Date: 08/17/2000
• Status: Expired due to Term

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Braun, Oliver, Meyer, Markus, Herzog, Markus, Huetsch, Matthias
• Primary Examiner(s): An; Meng-Ai
• Assistant Examiner(s): WU, QING YUAN
• Application Number:
  US09/932,717
• Publication Number:
  US 20020049842A1
• Time in Patent Office: 2,755 Days
• Field of Search: 718/105, 718/104, 709201-203, 709/208, 709/217, 709/223, 709/226, 370/238
• US Class Current: 718/105
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/1014 based on the content of a request
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

Load balancing method and system for balancing a processing load in a network, wherein load balancer upon receiving a client request selects one of a plurality of processing servers for serving the request. The selection of a processing server may be based on a location of a client and a processing server. The load balancer may comprise a load balancing master and a plurality of load balancing slaves, wherein the load balancing slaves receive client requests and transmit a selection request message to the load balancing master. The load balancing master selects a load balancing slave and/or a processing server for serving the request and generates a corresponding instruction message. The client request is served by the selected load balancing slave and the selected processing server by establishing a communication link between the client and the processing server. Service may involve execution of applications on the selected processing server under control of the client, for example word processors, scientific applications and similar.

Claims

1. A method for balancing a load in a network having a load balancing slave server, a load balancing master server, a plurality of processing servers, and a client, the method comprising the steps of:

selecting by the load balancing master server the load balancing slave server to receive a processing request from the client to perform a processing;

receiving at the load balancing slave server the processing request from the client to perform the processing, after the load balancing master server selects the load balancing slave server;

sending by the load balancing slave server a processing server request to the load balancing master server in response to the receipt of the processing request;

determining a load of each of the plurality of processing servers by the load balancing master server by receiving a load metric with the processing server request from the load balancing slave server at the load balancing master server;

selecting by the load balancing master server a selected one of the plurality of processing servers that is suitable for performing the processing responsive to the processing server request, wherein the selected one of the plurality of processing servers is selected based on the load of each of the plurality of processing servers;

sending an identifier of the selected one of the plurality of processing servers from the load balancing master server to the load balancing slave server; and

establishing by the load balancing slave server a communication link between the selected one of the plurality of processing servers and the client to perform the processing.

2. The method of claim 1, wherein the step of establishing further includes the step of:

routing the communication link between the selected one of the plurality of processing servers and the client through the load balancing slave server.

3. The method of claim 1, further comprising the step of:

receiving a plurality of load metrics from each of the plurality of processing servers.

4. A method in a data processing system having a first and a second load balancing server and having a plurality of processing servers, the method comprising the steps of:

selecting by the second load balancing server the first load balancing server to receive a processing request from a client to perform a processing;

receiving by the first load balancing server the processing request to perform the processing, after the second load balancing server selects the first load balancing server;

sending a processing server request from the first load balancing server to the second load balancing server;

determining a load of each of the plurality of processing servers by the second load balancing server;

selecting by the second load balancing server a selected one of the plurality of processing servers that is suitable for performing the processing responsive to the processing server request, wherein the selection is performed based on the load of each of the plurality of processing servers;

sending an identifier of the selected one of the plurality of processing servers from the second load balancing server to the first load balancing server; and

sending by the second load balancing server to the selected one of the plurality of processing servers an indication to perform the processing by identifying to the first load balancing server the selected one of the plurality of processing servers after the indication to perform the processing has been sent to the selected one of the plurality of processing servers.

5. The method of claim 4, further comprising the steps of:

receiving a plurality of load metrics that originate from the plurality of processing servers at the second load balancing server.

6. The method of claim 4, wherein sending the processing server request further includes the step of:

encoding at least one load metric in the processing server request.

7. The method of claim 4, wherein the first load balancing server is a load balancing slave.

8. The method of claim 4, wherein the second load balancing server is a load balancing master.

9. A data processing system, comprising:

a plurality of processing servers;

a client that sends a processing request;

a load balancing slave server that is selected by a load balancing master server to receive the processing request from the client after the load balancing slave server is selected, that sends processing server request to the load balancing master server for a selection of one of the plurality of processing servers that is suitable for performing a processing, that receives an indication of the selected one of the plurality of processing servers from the load balancing master server, and that establishes a communication link between the selected one of the plurality of processing servers and the client to perform the processing; and

the load balancing master server that selects the load balancing slave server to receive the processing request from the client after the load balancing slave server is selected, that receives a processing server request from the load balancing slave server, that determines a load of each of the plurality of processing servers, that selects the selected one of the plurality of processing servers based on the load of each of the plurality of processing servers responsive to the processing server request, and that sends the indication of the selected one of the plurality of processing servers to the load balancing slave server,

wherein at least one load metric is included in the processing server request sent by the load balancing slave server to the load balancing master server.

10. The data processing system of claim 9, wherein a plurality of load metrics are received at the load balancing master server from the plurality of processing servers that indicate the load on each of the plurality of processing servers.

11. A data processing system, comprising:

a plurality of processing servers;

a client that sends a processing request to have processing performed in a load balanced manner;

a first load balancing server that is selected by a second load balancing server to receive the processing request from the client and that receives the processing request from the client after the first load balancing server is selected; and

the second load balancing server that selects the first load balancing server to receive the processing request from the client, that receives a processing server request from the first load balancing server, that determines a load of each of the plurality of processing servers by receiving a load metric with the processing server request, that selects a selected one of the plurality of processing servers that is suitable for performing the processing in the load balanced manner responsive to the processing server request, and that sends to the selected one of the plurality of processing servers an indication to perform the processing, wherein the selection is based on the load of each of the plurality of processing servers.

12. The data processing system of claim 11, wherein the first load balancing server is a load balancing slave.

13. The data processing system of claim 11, wherein the second load balancing server is a load balancing master.

14. The data processing system of claim 11, wherein the second load balancing server is in receipt of a plurality of load metrics that originate from each of the plurality of processing servers and indicate the load on each of the plurality of processing servers.

15. A computer-readable medium containing instructions that cause a data processing system to perform a method for balancing a load in a network having a load balancing slave server, a load balancing master server, a plurality of processing servers, and a client, the method comprising the steps of:

selecting by the load balancing master server the load balancing slave server to receive a processing request from the client to perform a processing;

receiving at the load balancing slave server the processing request from the client to perform the processing after the load balancing master server selects the load balancing slave server;

sending by the load balancing slave server a processing server request to the load balancing master server in response to the receipt of the processing request;

determining a load of each of the plurality of processing servers by the load balancing master server by receiving a load metric with the processing server request from the load balancing slave server at the load balancing master server;

selecting by the load balancing master server a selected one of the plurality of processing servers that is suitable for performing the processing responsive to the processing server request, wherein the selected one of the plurality of processing servers is selected based on the load of each of the plurality of processing servers;

sending an identifier of the selected one of the plurality of processing servers from the load balancing master server to the load balancing slave server; and

establishing by the load balancing slave server a communication link between the selected one of the plurality of processing servers and the client to perform the processing.

16. The computer-readable medium of claim 15, wherein the step of establishing further includes the step of:

routing the communication link between the selected one of the plurality of processing servers and the client through the load balancing slave server.

17. The computer readable medium of claim 15, further comprising the step of:

receiving a plurality of load metrics from each of the plurality of processing servers.

18. A computer readable medium containing instructions that cause a data processing system to perform a method for load balancing having a first and a second load balancing server and having a plurality of processing servers, the method comprising the steps of:

selecting by the second load balancing server the first load balancing server to receive a processing request from a client to perform a processing;

receiving by the first load balancing server the processing request to perform the processing, after the second load balancing server selects the first load balancing server;

sending a processing server request from the first load balancing server to the second load balancing server;

determining a load of each of the plurality of processing servers by the second load balancing server;

selecting by the second load balancing server a selected one of the plurality of processing servers that is suitable for performing the processing responsive to the processing server request, wherein the selection is performed based on the load of each of the plurality of processing servers; and

sending by the second load balancing server to the selected one of the plurality of processing servers an indication to perform the processing by identifying to the first load balancing server the selected one of the plurality of processing servers after the indication to perform the processing has been sent to the selected one of the plurality of processing servers.

19. The computer-readable medium of claim 18, further comprising the steps of:

receiving a plurality of load metrics that originate from the plurality of processing servers at the second load balancing server.

20. The computer-readable medium of claim 18, wherein sending the processing server request further includes the step of:

encoding at least one load metric in the processing server request.

21. A load balancer for balancing a load in a network having a load balancing slave server, a load balancing master server, a plurality of processing servers, and a client, the load balancer comprising:

means for selecting by the load balancing master server the load balancing slave server to receive a processing request from a client to perform a processing;

means for receiving at the load balancing slave server the processing request from the client to perform the processing, after the load balancing master server selects the load balancing slave server;

means for sending by the load balancing slave server a processing server request to the load balancing master server in response to the receipt of the processing request;

means for determining a load of each of the plurality of processing servers by the load balancing master server by receiving a load metric with the processing server request from the load balancing slave server at the load balancing master server;

means for selecting by the load balancing master server a selected one of the plurality of processing servers that is suitable for performing the processing responsive to the processing server request, wherein the selected one of the plurality of processing servers is selected based on the load of each of the plurality of processing servers;

means for sending an identifier of the selected one of the plurality of processing servers from the load balancing master server to the load balancing slave server; and

means for establishing by the load balancing slave server a communication link between the selected one of the plurality of processing servers and the client to perform the processing.