DPL Release Notes

Changes and New Features

This section describes the changes and added features between preliminary release (Jan. 2025) and this beta v1.1.0 release. 

• Extern support for calculating a CRC32 hash over a custom set of header fields

• Extern for setting L2 Ethertype field and L3 protocol field

• Removal of externs to set and decrement IP TTL. These fields can be set directly with an assignment expression or decrement operator.

• Extern to push and pop new headers into the packet (experimental feature)

• Extern to force a reparse after pushing and popping headers

• Capability to add entries to a DPL table from the data plane based on the current packet (beta level feature)

• DPL table support for entry idle timeout. The timeout value can be set via P4Runtime.

• Support for delayed counter statistics that perform a lazy read of counter values

• Support for high update rate tables. These tables are managed via a DPL Runtime Controller SDK and not through P4Runtime. 

Capabilities and Limitations

P4 Runtime

• The size of any P4 table or counter object must be a power of 2 and smaller than 2²³

• The combined size of all P4 tables and counter objects must be smaller than 2²⁴

• A P4 table of size N allows for N-1 regular entries and 1 default entry

• P4 Controller support:

  • Only one P4 Controller can be connected to the DPL Runtime daemon at a given time

• RPC messages support:

  • Supported RPC messages:

    • Write RPC:

      • Only CONTINUE_ON_ERROR atomicity is supported

      • Batching is supported

      • Supported entities:

        • TableEntry

        • CounterEntry

        • DirectCounterEntry

        • MeterEntry

        • DirectMeterEntry

      • INSERT operation:

        • Supports regular entries only

      • DELETE operation:

        • Supports regular entries only

      • MODIFY operation:

        • Supports default entry only

        • Supports indirect and direct counter entry

        • Supports indirect and direct meter entryModemax cir/pirmax cburst/pburstBYTES255000000000       80000000PACKETS*  1992187500          625000* In packets modem, packet=128 bytes

    • Read RPC:

      • Batching is supported

      • Supported entities:

        • TableEntry

        • CounterEntry

        • DirectCounterEntry

        • MeterEntry

        • DirectMeterEntry

    • SetForwardingPipelineConfig RPC

    • GetForwardingPipelineConfig RPC

    • StreamChannel RPC

      • PacketIn

      • PacketOut

      • IdleTimeoutNotification

      • StreamError

  • Unsupported RPC messages:

    • Capabilities RPC

    • Unsupported entities:

      • ExternEntry

      • ActionProfileMember

      • ActionProfileGroup

      • PacketReplicationEngineEntry

      • ValueSetEntry

      • RegisterEntry

      • DigestEntry

    • Unsupported StreamChannel Request/Response updates:

      • MasterArbitrationUpdate

      • DigestList and DigestListAck

      • google.protobuf.Any

Bug Fixes

Known Issues

The following are known limitations of the DPL Runtime daemon service.

Last updated: May 11, 2025