Where is Metadata Stored?

Stateful Flow Management

Platform
Napatech SmartNIC
Content Type
User Guide
Capture Software Version
Link™ Capture Software 12.6

There are certain principles that apply when considering where to store flow metadata.

Metadata storage principles

  • Data should always be stored as close as possible to where it is needed.
  • Flow records in the SmartNIC contain only the information needed by the SmartNIC Fast Path.
  • Flow records in the application contain any information needed by the application to ensure:
    • Lowest PCI bandwidth, because there is less metadata per packet
    • Highest scalability, because memory is less limited in the host than in the SmartNIC
    • Highest flexibility, because the application can update flow records without a SmartNIC update
    • Highest performance, because the CPUs are being used for tasks they do best
  • The SmartNIC can provide a flow ID/PTR for every packet and flow record that is delivered to the application, ensuring the best acceleration for an application.