guides/prog_guide/index.rst

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Programmer's Guide
==================

June 2014


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**Contents**

.. toctree::
    :maxdepth: 3
    :numbered:

    intro
    overview
    env_abstraction_layer
    malloc_lib
    ring_lib
    mempool_lib
    mbuf_lib
    poll_mode_drv
    i40e_ixgbe_igb_virt_func_drv
    driver_vm_emul_dev
    ivshmem_lib
    poll_mode_drv_emulated_virtio_nic
    poll_mode_drv_paravirtual_vmxnets_nic
    intel_dpdk_xen_based_packet_switch_sol
    libpcap_ring_based_poll_mode_drv
    link_bonding_poll_mode_drv_lib
    timer_lib
    hash_lib
    lpm_lib
    lpm6_lib
    packet_distrib_lib
    ip_fragment_reassembly_lib
    multi_proc_support
    kernel_nic_interface
    thread_safety_intel_dpdk_functions
    qos_framework
    power_man
    packet_classif_access_ctrl
    packet_framework
    source_org
    dev_kit_build_system
    dev_kit_root_make_help
    extend_intel_dpdk
    build_app
    ext_app_lib_make_help
    perf_opt_guidelines
    writing_efficient_code
    profile_app
    glossary


**Figures**

:ref:`Figure 1. Core Components Architecture <pg_figure_1>`

:ref:`Figure 2. EAL Initialization in a Linux Application Environment <pg_figure_2>`

:ref:`Figure 3. Example of a malloc heap and malloc elements within the malloc library <pg_figure_3>`

:ref:`Figure 4. Ring Structure <pg_figure_4>`

:ref:`Figure 5. Two Channels and Quad-ranked DIMM Example <pg_figure_5>`

:ref:`Figure 6. Three Channels and Two Dual-ranked DIMM Example <pg_figure_6>`

:ref:`Figure 7. A mempool in Memory with its Associated Ring <pg_figure_7>`

:ref:`Figure 8. An mbuf with One Segment <pg_figure_8>`

:ref:`Figure 9. An mbuf with Three Segments <pg_figure_9>`

:ref:`Figure 10. Virtualization for a Single Port NIC in SR-IOV Mode <pg_figure_10>`

:ref:`Figure 11. Performance Benchmark Setup <pg_figure_11>`

:ref:`Figure 12. Fast Host-based Packet Processing <pg_figure_12>`

:ref:`Figure 13. Inter-VM Communication <pg_figure_13>`

:ref:`Figure 14. Host2VM Communication Example Using kni vhost Back End <pg_figure_14>`

:ref:`Figure 15. Host2VM Communication Example Using qemu vhost Back End <pg_figure_15>`

:ref:`Figure 16. Memory Sharing inthe Intel® DPDK Multi-process Sample Application <pg_figure_16>`

:ref:`Figure 17. Components of an Intel® DPDK KNI Application <pg_figure_17>`

:ref:`Figure 18. Packet Flow via mbufs in the Intel DPDK® KNI <pg_figure_18>`

:ref:`Figure 19. vHost-net Architecture Overview <pg_figure_19>`

:ref:`Figure 20. KNI Traffic Flow <pg_figure_20>`

:ref:`Figure 21. Complex Packet Processing Pipeline with QoS Support <pg_figure_21>`

:ref:`Figure 22. Hierarchical Scheduler Block Internal Diagram <pg_figure_22>`

:ref:`Figure 23. Scheduling Hierarchy per Port <pg_figure_23>`

:ref:`Figure 24. Internal Data Structures per Port <pg_figure_24>`

:ref:`Figure 25. Prefetch Pipeline for the Hierarchical Scheduler Enqueue Operation <pg_figure_25>`

:ref:`Figure 26. Pipe Prefetch State Machine for the Hierarchical Scheduler Dequeue Operation <pg_figure_26>`

:ref:`Figure 27. High-level Block Diagram of the Intel® DPDK Dropper <pg_figure_27>`

:ref:`Figure 28. Flow Through the Dropper <pg_figure_28>`

:ref:`Figure 29. Example Data Flow Through Dropper <pg_figure_29>`

:ref:`Figure 30. Packet Drop Probability for a Given RED Configuration <pg_figure_30>`

:ref:`Figure 31. Initial Drop Probability (pb), Actual Drop probability (pa) Computed Using a Factor 1 (Blue Curve) and a Factor 2 (Red Curve) <pg_figure_31>`

:ref:`Figure 32. Example of packet processing pipeline. The input ports 0 and 1 are connected with the output ports 0, 1 and 2 through tables 0 and 1. <pg_figure_32>`

:ref:`Figure 33. Sequence of steps for hash table operations in packet processing context <pg_figure_33>`

:ref:`Figure 34. Data structures for configurable key size hash tables <pg_figure_34>`

:ref:`Figure 35. Bucket search pipeline for key lookup operation (configurable key size hash tables) <pg_figure_35>`

:ref:`Figure 36. Pseudo-code for match, match_many and match_pos <pg_figure_36>`

:ref:`Figure 37. Data structures for 8-byte key hash tables <pg_figure_37>`

:ref:`Figure 38. Data structures for 16-byte key hash tables <pg_figure_38>`

:ref:`Figure 39. Bucket search pipeline for key lookup operation (single key size hash tables) <pg_figure_39>`

**Tables**

:ref:`Table 1. Packet Processing Pipeline Implementing QoS <pg_table_1>`

:ref:`Table 2. Infrastructure Blocks Used by the Packet Processing Pipeline <pg_table_2>`

:ref:`Table 3. Port Scheduling Hierarchy <pg_table_3>`

:ref:`Table 4. Scheduler Internal Data Structures per Port <pg_table_4>`

:ref:`Table 5. Ethernet Frame Overhead Fields <pg_table_5>`

:ref:`Table 6. Token Bucket Generic Operations <pg_table_6>`

:ref:`Table 7. Token Bucket Generic Parameters <pg_table_7>`

:ref:`Table 8. Token Bucket Persistent Data Structure <pg_table_8>`

:ref:`Table 9. Token Bucket Operations <pg_table_9>`

:ref:`Table 10. Subport/Pipe Traffic Class Upper Limit Enforcement Persistent Data Structure <pg_table_10>`

:ref:`Table 11. Subport/Pipe Traffic Class Upper Limit Enforcement Operations <pg_table_11>`

:ref:`Table 12. Weighted Round Robin (WRR) <pg_table_12>`

:ref:`Table 13. Subport Traffic Class Oversubscription <pg_table_13>`

:ref:`Table 14. Watermark Propagation from Subport Level to Member Pipes at the Beginning of Each Traffic Class Upper Limit Enforcement Period <pg_table_14>`

:ref:`Table 15. Watermark Calculation <pg_table_15>`

:ref:`Table 16. RED Configuration Parameters <pg_table_16>`

:ref:`Table 17. Relative Performance of Alternative Approaches <pg_table_17>`

:ref:`Table 18. RED Configuration Corresponding to RED Configuration File <pg_table_18>`

:ref:`Table 19. Port types <pg_table_19>`

:ref:`Table 20. Port abstract interface <pg_table_20>`

:ref:`Table 21. Table types <pg_table_21>`

:ref:`Table 29. Table Abstract Interface <pg_table_29_1>`

:ref:`Table 22. Configuration parameters common for all hash table types <pg_table_22>`

:ref:`Table 23. Configuration parameters specific to extendible bucket hash table <pg_table_23>`

:ref:`Table 24. Configuration parameters specific to pre-computed key signature hash table <pg_table_24>`

:ref:`Table 25. The main large data structures (arrays) used for configurable key size hash tables <pg_table_25>`

:ref:`Table 26. Field description for bucket array entry (configurable key size hash tables) <pg_table_26>`

:ref:`Table 27. Description of the bucket search pipeline stages (configurable key size hash tables) <pg_table_27>`

:ref:`Table 28. Lookup tables for match, match_many, match_pos <pg_table_28>`

:ref:`Table 29. Collapsed lookup tables for match, match_many and match_pos <pg_table_29>`

:ref:`Table 30. The main large data structures (arrays) used for 8-byte and 16-byte key size hash tables <pg_table_30>`

:ref:`Table 31. Field description for bucket array entry (8-byte and 16-byte key hash tables) <pg_table_31>`

:ref:`Table 32. Description of the bucket search pipeline stages (8-byte and 16-byte key hash tables) <pg_table_32>`

:ref:`Table 33. Next hop actions (reserved) <pg_table_33>`

:ref:`Table 34. User action examples <pg_table_34>`