L3 Forwarding in a Virtualization Environment Sample Application
================================================================
-The L3 Forwarding in a Virtualization Environment sample application is a simple example of packet processing using the Intel® DPDK.
+The L3 Forwarding in a Virtualization Environment sample application is a simple example of packet processing using the DPDK.
The application performs L3 forwarding that takes advantage of Single Root I/O Virtualization (SR-IOV) features
in a virtualized environment.
Overview
--------
-The application demonstrates the use of the hash and LPM libraries in the Intel® DPDK to implement packet forwarding.
-The initialization and run-time paths are very similar to those of the L3 forwarding application
-(see Chapter 10 "L3 Forwarding Sample Application" for more information).
+The application demonstrates the use of the hash and LPM libraries in the DPDK to implement packet forwarding.
+The initialization and run-time paths are very similar to those of the :doc:`l3_forward`.
The forwarding decision is taken based on information read from the input packet.
The lookup method is either hash-based or LPM-based and is selected at compile time.
.. note::
- Please refer to Section 9.1.1 "Virtual Function Setup Instructions" for virtualized test case setup.
+ Please refer to :ref:`l2_fwd_vf_setup` for virtualized test case setup.
Compiling the Application
-------------------------
export RTE_TARGET=x86_64-native-linuxapp-gcc
- See the *Intel® DPDK Getting Started Guide* for possible RTE_TARGET values.
+ See the *DPDK Getting Started Guide* for possible RTE_TARGET values.
#. Build the application:
* --no-numa: optional, disables numa awareness
-For example, consider a dual processor socket platform where cores 0,2,4,6, 8, and 10 appear on socket 0,
-while cores 1,3,5,7,9, and 11 appear on socket 1.
-Let's say that the programmer wants to use memory from both NUMA nodes,
-the platform has only two ports and the programmer wants to use one core from each processor socket to do the packet processing
-since only one Rx/Tx queue pair can be used in virtualization mode.
+For example, consider a dual processor socket platform with 8 physical cores, where cores 0-7 and 16-23 appear on socket 0,
+while cores 8-15 and 24-31 appear on socket 1.
-To enable L3 forwarding between two ports, using one core from each processor,
-while also taking advantage of local memory accesses by optimizing around NUMA,
-the programmer can pin to the appropriate cores and allocate memory from the appropriate NUMA node.
-This is achieved using the following command:
+To enable L3 forwarding between two ports, assuming that both ports are in the same socket, using two cores, cores 1 and 2,
+(which are in the same socket too), use the following command:
.. code-block:: console
- ./build/l3fwd-vf -c 0x03 -n 3 -- -p 0x3 --config="(0,0,0),(1,0,1)"
+ ./build/l3fwd-vf -l 1,2 -n 4 -- -p 0x3 --config="(0,0,1),(1,0,2)"
In this command:
-* The -c option enables cores 0 and 1
+* The -l option enables cores 1 and 2
* The -p option enables ports 0 and 1
* The --config option enables one queue on each port and maps each (port,queue) pair to a specific core.
- Logic to enable multiple RX queues using RSS and to allocate memory from the correct NUMA nodes
- is included in the application and is done transparently.
The following table shows the mapping in this example:
+----------+-----------+-----------+------------------------------------+
| **Port** | **Queue** | **lcore** | **Description** |
| | | | |
+==========+===========+===========+====================================+
- | 0 | 0 | 0 | Map queue 0 from port 0 to lcore 0 |
+ | 0 | 0 | 1 | Map queue 0 from port 0 to lcore 1 |
| | | | |
+----------+-----------+-----------+------------------------------------+
- | 1 | 1 | 1 | Map queue 0 from port 1 to lcore 1 |
+ | 1 | 0 | 2 | Map queue 0 from port 1 to lcore 2 |
| | | | |
+----------+-----------+-----------+------------------------------------+
-Refer to the *Intel® DPDK Getting Started Guide* for general information on running applications
+Refer to the *DPDK Getting Started Guide* for general information on running applications
and the Environment Abstraction Layer (EAL) options.
Explanation
-----------
The operation of this application is similar to that of the basic L3 Forwarding Sample Application.
-See Section 10.4 "Explanation" for more information.
+See :ref:`l3_fwd_explanation` for more information.