Onboard SDRAM

Napatech Link-Capture™ Software Features
Platform
Napatech SmartNIC
Content Type
Feature Description
Capture Software Version
Link™ Capture Software 12.12

SDRAM requirement

Frames from the receive pipeline can be stored in onboard SDRAM before transferred to the host memory, if needed, in order to await available host memory transfer.

Total memory size

The total memory size for all buffers in the onboard SDRAM is:

  • NT400D11: 12 Gbytes
  • NT200A02: 12 Gbytes
  • NT100A01: 8 Gbytes
  • NT50B01: 10 Gbytes
  • NT40A11: 4 Gbytes
  • NT40A01: 4 Gbytes
  • NT40E3-4-PTP: 4 Gbytes
  • NT20E3-2-PTP: 4 Gbytes
Note: The total memory size of the onboard SDRAM for all buffers in the NT400D11 and NT200A02 SmartNICs is 12 Gbytes. For these SmartNICs running the flow management 1 image, only 1.5-Gbyte memory is allocated for packet buffering, while 10.5-Gbyte memory is used for the flow table by default. The SDRAM memory allocation between packet buffering and the flow table is configurable using the SDRAMSplit parameter in the ntservice.ini file.
Note: The total memory size of the onboard SDRAM for all buffers in the NT100A01 SmartNICs is 8 Gbytes. For these SmartNICs running the flow management 1 image, only 1-Gbyte memory is used for packet buffering, while 7-Gbyte memory is used for the flow table by default. The SDRAM memory allocation between packet buffering and the flow table is configurable using the SDRAMSplit parameter in the ntservice.ini file.

Protection of frames in onboard memory

Frames stored in the onboard SDRAM are protected by a CRC, in order to detect any data error. One or more frames are discarded in case of any CRC error, depending on the error type.

The number of discarded frames can be derived from the ingress and egress counters, once the traffic is stopped and the SDRAM is emptied.

SDRAM fill level events

Four specific SDRAM fill levels can be defined in the ntservice.ini file (see DN-0449). If the SDRAM is filled above one of these levels, an event is triggered. If the fill level decreases below one of these levels minus 10%, an event is triggered.