Method and system for requester virtual cut through

• US 9,118,597 B2
• Filed: 07/31/2014
• Issued: 08/25/2015
• Est. Priority Date: 08/23/2011
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Bugge, Haakon Ording, Huse, Lars Paul, Toerudbakken, Ola
• Primary Examiner(s): MARCELO, MELVIN C
• Application Number:
  US14/449,027
• Publication Number:
  US 20140341229A1
• Time in Patent Office: 390 Days
• Field of Search: 370/470, 370/471
• US Class Current: 1/1
• CPC Class Codes: H04L 12/6418 Hybrid transport
• CPC Class Codes: H04L 47/36 by determining packet size, e.g. maximum transfer unit [MTU]
• CPC Class Codes: H04L 47/365 Dynamic adaptation of the packet size

Abstract

A method for transmitting a message includes a communication adapter receiving, from a transmitting device, a request to send the message. The method further includes modifying a maximum transfer unit (MTU) to obtain a modified MTU, transmitting, from the communication adapter to a receiving system, a first sub-unit of the message using the modified MTU, iteratively increasing the MTU for transmitting intermediate sub-units of the message until an MTU limit is reached, and transmitting, to the receiving system, the intermediate sub-units of the message. The intermediate sub-units are transmitted after the first sub-unit and before a second sub-unit. The method further includes transmitting, from the communication adapter to the receiving system, the second sub-unit to the receiving system using a full path MTU.

Claims

1. A method for transmitting a message, the method comprising:

receiving, by a collect buffer unit of a host channel adapter (HCA), from a transmitting device, a request to send the message;

temporarily storing, by a virtual kick module of the HCA, the request once the request is received;

obtaining, by a queue pair fetch module of the HCA, a queue pair status information corresponding to the request;

obtaining, by a direct memory access (DMA) module of the HCA, the message from a location in memory of the transmitting device, wherein the location is specified in the request;

modifying a maximum transfer unit (MTU) to obtain a modified MTU;

transmitting, from the HCA to a receiving system, a first sub-unit of the message using the modified MTU;

iteratively increasing the MTU for transmitting a plurality of intermediate sub-units of the message until an MTU limit is reached;

transmitting, to the receiving system, the plurality of intermediate sub-units of the message, wherein the plurality of intermediate sub-units are transmitted after the first sub-unit and before a second sub-unit; and

transmitting, from the HCA to the receiving system, the second sub-unit to the receiving system using a full path MTU.

2. The method of claim 1, further comprising:

after transmitting the second sub-unit, iteratively decreasing the maximum transfer unit (MTU) for transmitting a plurality of remaining sub-units of the message.

3. The method of claim 1, further comprising:

selecting the modified MTU to use for the transmission of the message based on a size of the message.

4. The method of claim 1, wherein the full path MTU is greater than the modified MTU, the method further comprising:

for each subsequent sub-unit of the message, selecting a selected MTU from a group consisting of the modified MTU and the full path MTU to transmit the subsequent sub-unit of the message.

5. The method of claim 1, wherein the receiving system uses stateful ingress filtering to deteimine the modified MTU of the first sub-unit on a per request basis.

6. The method of claim 1, wherein the modified MTU is encoded into the first sub-unit.

7. A non-transitory computer readable medium storing instructions for transmitting a message, the instructions comprising functionality to:

receive, by a collect buffer unit of a host channel adapter (HCA), from a transmitting device, a request to send the message;

temporarily store, by a virtual kick module of the HCA, the request once the request is received;

obtain, by a queue pair fetch module of the HCA, a queue pair status information corresponding to the request;

obtain, by a direct memory access (DMA) module of the HCA, the message from a location in memory of the transmitting device, wherein the location is specified in the request;

modify a maximum transfer unit (MTU) to obtain a modified MTU;

transmit, to a receiving system, a first sub-unit of the message using the modified MTU;

iteratively increase the MTU for transmitting a plurality of intermediate sub-units of the message until an MTU limit is reached;

transmit, from the HCA to the receiving system, the plurality of intermediate sub-units of the message, wherein the plurality of intermediate sub-units are transmitted after the first sub-unit and before a second sub-unit; and

transmit, from the HCA to the receiving system, the second sub-unit to the receiving system using a full path MTU.

8. The non-transitory computer readable medium of claim 7, wherein the instructions further comprise functionality to:

after transmitting the second sub-unit, iteratively decrease the maximum transfer unit (MTU) for transmitting a plurality of remaining sub-units of the message.

9. The non-transitory computer readable medium of claim 7, wherein the instructions further comprise functionality to:

select the modified MTU to use for the transmission of the message based on a size of the message.

10. The non-transitory computer readable medium of claim 7, wherein the modified MTU is encoded into the first sub-unit.

11. The non-transitory computer readable medium of claim 7, wherein the full path MTU is greater than the modified MTU, the instructions further comprise functionality to:

for each subsequent sub-unit of the message, selecting a selected MTU from a group consisting of the modified MTU and the full path MTU to transmit the subsequent sub-unit of the message.