Priority based flow control within a virtual distributed bridge environment

• US 8,644,139 B2
• Filed: 04/26/2010
• Issued: 02/04/2014
• Est. Priority Date: 04/26/2010
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Armstrong, William J., Basso, Claude, Verrilli, Colin B.
• Primary Examiner(s): Thier, Michael
• Assistant Examiner(s): MENSAH, PRINCE AKWASI
• Application Number:
  US12/767,543
• Publication Number:
  US 20110261687A1
• Time in Patent Office: 1,380 Days
• Field of Search: 370229-240
• US Class Current: 370/229
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 47/17 Interaction among intermediate nodes, e.g. hop by hop
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/266 Stopping or restarting the source, e.g. X-on or X-off
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 49/602 Multilayer or multiprotocol switching, e.g. IP switching
• CPC Class Codes: H04L 49/70 Virtual switches

Abstract

Systems and methods to communicate data frames are provided. A particular apparatus may include a first adapter having a first queue configured to store a data frame associated with a first priority. The adapter is configured to generate a first priority pause frame. A distributed virtual bridge may be coupled to the first adapter. The distributed virtual bridge may include an integrated switch router and a first transport layer module configured to provide a frame-based interface to the integrated switch router. The transport layer module may include a first buffer associated with the first priority. A first bridge element of the distributed virtual bridge may be coupled to the first adapter queue and to the first transport layer module. The first bridge element is configured to receive the first priority pause frame from the adapter and to communicate an interrupt signal to the first transport layer module to interrupt delivery of the data frame to the first queue.

Claims

1. An apparatus, comprising:

a first adapter comprising a first queue that corresponds to a first priority and a second queue that corresponds to a second priority, wherein the first queue is configured to store a first data frame associated with the first priority, wherein the second queue is configured to store a second data frame associated with the second priority, and wherein the first adapter is configured to generate a first priority pause frame; and

a distributed virtual bridge coupled to the first adapter, the distributed virtual bridge comprising;

an integrated switch router;

a first transport layer module configured to;

provide a frame-based interface to the integrated switch router;

receive the first data frame from a second transport layer module via the integrated switch router; and

receive the second data frame from the second transport layer module via the integrated switch router, wherein the first transport layer module includes a first buffer associated with the first priority and a second buffer associated with the second priority; and

a first bridge element coupled to the first adapter and to the first transport layer module, wherein the first bridge element is configured to;

receive the first priority pause frame from the first adapter, wherein receipt of the first priority pause frame initiates generation of a first interrupt signal;

communicate the first interrupt signal to the first transport layer module to interrupt delivery of the first data frame to the first queue

wherein while the delivery of the first data frame is interrupted, the second data frame associated with the second priority is received from the first transport layer module and the second data frame is forwarded from the first transport layer module to the second queue.

2. The apparatus of claim 1, wherein the first priority pause frame is communicated to the first bridge element in response to the first queue reaching a particular threshold capacity.

3. The apparatus of claim 1, wherein transmission of the second data frame is unaffected by the first priority pause frame.

4. The apparatus of claim 1, wherein the second transport layer module includes a third buffer configured to store data frames associated with the first priority.

5. The apparatus of claim 4, wherein the first transport layer module communicates with the second transport layer module regarding a status of the first buffer of the first transport layer module using a credit exchange system.

6. The apparatus of claim 4, wherein the distributed virtual bridge further comprises a second bridge element coupled to the second transport layer module.

7. The apparatus of claim 6, wherein the second bridge element is configured to generate a second priority pause frame to interrupt delivery of the data frames associated with the first priority to the second buffer.

8. The apparatus of claim 7, wherein the second bridge element is configured to communicate the second priority pause frame to a second adapter coupled to the second bridge element, wherein the second adapter is configured to transmit the data frames associated with the first priority.

9. The apparatus of claim 1, wherein the first adapter includes a plurality of queues associated with a plurality of priorities.

10. The apparatus of claim 1, wherein the distributed virtual bridge further comprises a controlling bridge coupled to the first bridge element, the controlling bridge configured to program the first bridge element.

11. The apparatus of claim 1, wherein the first bridge element is configured to identify the first priority associated with the first data frame.

12. A method of managing data frame traffic flow, the method comprising:

receiving at a node of a distributed virtual bridge, the node comprising a bridge element and a first transport layer module, a first priority pause frame from a first adapter, wherein the first priority pause frame is generated by the first adapter in response to detecting a status of a first queue of the first adapter, the first queue configured to store a first data frame associated with a first priority, wherein receipt of the first priority pause frame from the first adapter initiates generation of a first interrupt signal at the bridge element;

receiving the first data frame at the first transport layer module from a second transport layer module via an integrated switch router;

communicating a first interrupt signal from the bridge element to the first transport layer module to interrupt delivery of the first data frame to the first queue;

receiving, while delivery of the first data frame is interrupted, a second data frame associated with a second priority at the first transport layer module from the second transport layer module via the integrated switch router;

forwarding the second data frame from the first transport layer to the first adapter; and

wherein the distributed virtual bridge is coupled to the first adapter, the distributed virtual bridge comprises the integrated switch router and the second transport layer module, wherein the bridge element is coupled to the first adapter and to the first transport layer module, and wherein the first transport layer module includes a first buffer associated with the first priority.

13. The method of claim 12, wherein the first transport layer module is configured to provide a frame-based interface to the integrated switch router.

14. The method of claim 12, further comprising determining from the first priority pause frame that the first queue has reached a particular threshold capacity.

15. The method of claim 12, further comprising using a credit exchange system to communicate a status of the first buffer of the first transport layer module to the second transport layer module.

16. The method of claim 15, further comprising interrupting a delivery of a third data frame associated with the first priority from the second transport layer module.

17. The method of claim 16, further comprising generating a second priority pause frame at a bridge element coupled to the second transport layer module.

19. The method of claim 15, wherein the distributed virtual bridge further comprises the second transport layer module coupled to the integrated switch router, and wherein the second transport layer module includes a second buffer configured to store the data frames associated with the first priority.

18. A program product, comprising:

program code executable at a node of a distributed virtual bridge, the node comprising a bridge element and a first transport layer module;

to receive a priority pause frame from an adapter, wherein the priority pause frame is generated by the adapter in response to detecting a status of a queue configured to store a first data frame associated with a first priority, wherein receipt of the priority pause frame from the adapter initiates generation of an interrupt signal at the bridge element;

to communicate the interrupt signal to the first transport layer module, wherein the interrupt signal is configured to interrupt delivery of the first data frame to the queue;

to receive the first data frame at the first transport layer module from a second transport layer module via an integrated switch router;

to receive, while delivery of the first data frame is interrupted, a second data frame associated with a second priority at the first transport layer module from the second transport layer module via the integrated switch router; and

to forward the second data frame to the adapter, wherein the distributed virtual bridge is coupled to the adapter, the distributed virtual bridge comprises the integrated switch router and the second transport layer module, wherein the bridge element is coupled to the adapter and to the first transport layer module, and wherein the first transport layer module includes a buffer associated with the first priority; and

a computer readable storage device bearing the program code.