Network Interface Device

• US 20170187605A1
• Filed: 12/20/2016
• Published: 06/29/2017
• Est. Priority Date: 12/29/2015
• Status: Active Grant

• Current Assignee: Xilinx, Inc. (Advanced Micro Devices, Inc.)
• Original Assignee: SolarFlare Communications Incorporated (Advanced Micro Devices, Inc.)
• Inventors: Roberts, Derek, Riddoch, David J., Pope, Steven L.
• Granted Patent: US 11,165,683 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices
• CPC Class Codes: G06F 15/167 using a common memory, e.g. mailbox
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/263 Rate modification at the source after receiving feedback
• CPC Class Codes: H04L 47/29 using a combination of thresholds
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames

Abstract

A network interface device, said network interface device has a data transmission path configured to receive data for transmission. The data for transmission is to be sent over a network by the network interface device. A monitor is configured to monitor the data transmission path to determine if an underrun condition is associated with the data transmission path. If so, an indication is included in the transmitted data packet.

Claims

1. A network interface device, said network interface device comprising:

a data transmission path configured to receive data for transmission, said data for transmission to be sent over a network by said network interface device, a threshold being associated with said data transmission path; and

a monitor configured to monitor said data transmission path using said threshold to determine if an underrun condition is associated with said data transmission path and if so to transmit said data with an indication which indicates that said data is invalid.

2. The network interface as claimed in claim 1, wherein said threshold is adjustable.

3. The network interface as claimed in claim 1, wherein a plurality of data queues are provided, each data queue having a respective threshold.

4. The network interface as claimed in claim 3, wherein the threshold associated with each data transmission path may be individually selectable.

5. The network interface device as claimed in claim 1, wherein a plurality of different thresholds are available for selection, said network interface device having a memory configured to store different threshold information.

6. The network interface device as claimed in claim 5, wherein the threshold information comprises one or more parameters to be applied for a respective threshold.

7. The network interface as claimed in claim 5, wherein a plurality of data queues are provided, each data queue having a respective threshold, the memory being configured to store for each queue the associated threshold information and/or threshold.

8. The network interface device as claimed in claim 1, wherein the threshold is defined by a quality of service.

9. The network interface device as claimed in claim 1, comprising a threshold monitoring function which is configured to determine in dependence on an amount of data transmitted with said indication if a defined threshold is being met and if not, the threshold monitoring function is configured to adjust one or more threshold parameters.

10. The network interface device as claimed in claim 1, wherein the network interface device is configured to cause transmission of one or more packets to be aborted in response to information received from host processing device, said network interface device being configured such that said packet is discarded and no retransmission of said packet is attempted.

11. A network interface as claimed in claim 1, wherein in response to determination of said underrun condition, said monitor is configured to cause said indication to be provided in a packet which is to be transmitted, said packet comprising at least some of said data for transmission.

12. A network interface device as claimed in claim 1, wherein said indication is provided by one or more bits of a cyclic redundancy check and/or by a known value.

13. A network interface device as claimed in claim 1, further comprising a medium access control function, said monitor configured to cause said medium access control function to cause said indication to be provided in said packet.

14. A network interface device as claimed in claim 1, further comprising a physical layer function, said monitor configured to cause said physical layer function to cause said indication to be provided in said packet.

15. A network interface device as claimed in claim 1, wherein said monitor is configured to cause said data for transmission which has been transmitted with said indication to be retransmitted.

16. A network interface device as claimed in claim 15, wherein said network interface is configured to perform a direct memory access to obtain said data which is to be retransmitted.

17. A network interface device as claimed in claim 1, further comprising consumer queue information comprising a pointer which is updated in response to transmission of a packet, wherein said monitor is configured to cause the pointer not to be incremented if said packet to be transmitted comprises said indication.

18. A network interface device as claimed in claim 1, wherein said monitor is configured to determine an underrun condition associated with said transmit data path in response to one of:

a data rate of data being received being less than said threshold defining a threshold rate; and

a quantity of data in said data transmission path being less than said threshold defining a threshold amount.

19. A network interface device as claimed in claim 1, wherein data transmission path comprises a buffer, said data transmission path being configured such that transmission of data starts when at least N bytes of data is in said buffer, N being defined in dependence on said threshold.

20. A method comprising:

receiving data for transmission, said data for transmission to be sent over a network by a network interface device, a threshold being associated with said data transmission path;

monitoring said data using said threshold to determine if an underrun condition is associated with said data for transmission; and

if so, to cause an indication to be provided in a transmitted packet.