SYSTEMS AND METHODS FOR IDENTIFYING A PROCESSOR FROM A PLURALITY OF PROCESSORS TO PROVIDE SYMMETRICAL REQUEST AND RESPONSE PROCESSING

• US 20100287227A1
• Filed: 06/22/2009
• Published: 11/11/2010
• Est. Priority Date: 05/05/2009
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: Kurma, Jyotheesh, Goel, Deepak, Gopinath, Sandhya
• Granted Patent: US 8,990,431 B2
• Time in Patent Office: Days
• US Class Current: 709/202
• CPC Class Codes: G06F 9/45533 Hypervisors; Virtual machine monitors
• CPC Class Codes: H04L 47/33 using forward notification
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1023 based on a hash applied to IP addresses or costs
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54

Abstract

Described herein is a method and system for distributing request and responses across a multi-core system. Each core executes a packet engine that further processes data packets allocated to that core. A flow distributor executing within the multi-core system forwards client requests to a packet engine on a core that is selected based on a value generated when a hash is applied to a tuple comprising a client IP address, a client port, a server IP address and a server port identified in the request. The packet engine selects a first IP address and a first port of the core, and determines whether a hash of a tuple comprising those values identifies the selected core. A modification is then made to the client request so that the client request includes a tuple comprising the first IP address, the server IP address, the first port and the server port.

Claims

1. A method for providing symmetrical request and response processing across a packet engine of a plurality of packet engines, each of the plurality of packet engines executing on a respective core of a plurality of cores in a multi-core system intermediary to a client and a server, the method comprising:

a) receiving, by a packet engine on a first core of the multi-core system intermediary to a client and a server, from a flow distributor, a request of the client to the server, the first core selected by the flow distributor based on a hash of a first tuple comprising a client internet protocol address, a client port, a server internet protocol address and a server port identified in the request;

b) selecting, by the packet engine, a first internet protocol address of one or more internet protocol addresses of the first core and a first port from a plurality of ports of the first core;

c) determining, by the packet engine, that a hash of a second tuple comprising at least the first internet protocol address and the first port, identifies the first core;

d) identifying, by the packet engine, that the first port is available; and

e) modifying, by the packet engine, the request of the client to identify the first internet protocol address as the client internet protocol address and the first port as the client port.

2. The method of claim 1, wherein step (e) further comprises transmitting, by the packet engine, the modified request of the client to the server.

3. The method of claim 1, further comprising receiving, by the flow distributor, a response from the server to the request of the client, and distributing, by the flow distributor, the response to the first core of the packet engine based on the hash of a third tuple comprising a client internet protocol address, a client port, a server internet protocol address and a server port identified in the response.

4. The method of claim 1, wherein step (c) further comprises determining, by the packet engine, that the hash of the first tuple identifies the first core on which the packet engine executes.

5. The method of claim 1, wherein step (c) further comprises determining, by the packet engine, that the hash of the second tuple identifies the first core on which the packet engine executes.

6. The method of claim 1, wherein step (d) further comprises:

determining, by the packet engine, that the first port is not available;

selecting, by the packet engine, a second port from the plurality of ports of the first core;

determining, by the packet engine, that the second port is available;

determining, by the packet engine, that a hash of a fourth tuple comprising at least the first internet protocol address and the second port, identifies the first core; and

modifying, by the packet engine, the request of the client to identify the first internet protocol address as the client internet protocol address and the second port as the client port.

7. The method of claim 1, wherein step (d) further comprises:

determining, by the packet engine, that the first port is not available;

selecting, by the packet engine, a second internet protocol address from the one or more internet protocol addresses of the first core;

selecting, by the packet engine, a second port from the plurality of ports of the first core;

determining, by the packet engine, that a hash of a fifth tuple comprising at least the second internet protocol address and the second port, identifies the first core; and

modifying, by the packet engine, the request of the client to identify the second internet protocol address as the client internet protocol address and the second port as the client port.

8. The method of claim 1, wherein step (b) further comprises selecting a first internet protocol address from a group of predetermined internet protocol addresses of the first core.

9. The method of claim 1, wherein the flow distributor executes within the multi-core system.

10. The method of claim 1, wherein step (b) further comprises selecting a first port from a port table comprising available ports.

11. The method of claim 10, further comprising selecting each port for inclusion in the port table based in part on one or more hashes of local internet protocol addresses of a first core and local ports associated with each local internet protocol address.

12. The method of claim 1, further comprising a multi-core system comprising at least two cores, each core storing a port table comprising available ports on that core.

13. The method of claim 1, wherein the first core is selected by the flow distributor based in part on the hash of the first tuple.

14. The method of claim 1, further comprising updating a port allocation table to indicate the assignment of the first port to the data packet.

15. A system for providing symmetrical request and response processing across a packet engine of a plurality of packet engines, each of the plurality of packet engines executing on a respective core of a plurality of cores in a multi-core system intermediary to a client and a server, the system comprising:

a multi-core system intermediary to a client and a server, the multi-core system comprising a plurality of cores;

a flow distributor receiving a request of a client to a server, and selecting a first core based on a hash of a first tuple comprising a client internet protocol address, a client port, a server internet protocol address and a server port identified in the client request; and

a packet engine executing on a first core of the multi-core system, the packet engine;

receiving the client request,

selecting a first internet protocol address of one or more internet protocol addresses of the first core and a first port from a plurality of ports of the first core,

determining that a hash of a second tuple comprising at least the first internet protocol address and the first port, identifies the first core,

identifying that the first port is available, and

modifying the client request to identify the first internet protocol address as the client internet protocol address and the first port as the client port.

16. The system of claim 15, wherein the packet engine transmits the modified request of the client to the server.

17. The system of claim 15, wherein the flow distributor:

receives a response from the server to the request of the client; and

distributes the response to the first core of the packet engine based on the hash of a third tuple comprising a client internet protocol address, a client port, a server internet protocol address and a server port identified in the response.

18. The system of claim 15, wherein the packet engine determines that the hash of the first tuple identifies the first core on which the packet engine executes.

19. The system of claim 15, wherein the packet engine determines that the hash of the second tuple identifies the first core on which the packet engine executes.

20. The system of claim 15, wherein the packet engine:

determines that the first port is not available;

selects a second port from the plurality of ports of the first core;

determines that the second port is available;

determines that a hash of a fourth tuple comprising at least the first internet protocol address and the second port, identifies the first core; and

modifies the request of the client to identify the first internet protocol address as the client internet protocol address and the second port as the client port.

21. The system of claim 15, wherein the packet engine:

determines that the first port is not available;

selects a second internet protocol address from the one or more internet protocol addresses of the first core;

selects a second port from the plurality of ports of the first core;

determines that a hash of a fifth tuple comprising at least the second internet protocol address and the second port, identifies the first core; and

modifies the request of the client to identify the second internet protocol address as the client internet protocol address and the second port as the client port.

22. The system of claim 15, wherein the packet engine selects a first internet protocol address from a group of predetermined internet protocol addresses of the first core.

23. The system of claim 15, wherein the flow distributor executes within the multi-core system.

24. The system of claim 15, wherein the packet engine selects a first port from a port table comprising available ports.

25. The system of claim 24, wherein the packet engine selects each port for inclusion in the port table based in part on one or more hashes of local internet protocol addresses of a first core and local ports associated with each local internet protocol address.

26. The system of claim 15, wherein the multi-core system comprises at least two cores, each core storing a port table comprising available ports on that core.

27. The system of claim 15, wherein the first core is selected by the flow distributor based in part on the hash of the first tuple.

28. The system of claim 15, further comprising a port allocation table updated to indicate the assignment of the first port to the data packet.