VPP Startup Settings

CSIT code manipulates a number of VPP settings in startup.conf for optimized performance. List of common settings applied to all tests and test dependent settings follows.

See VPP startup.conf for a complete set and description of listed settings.

Common Settings

List of vpp startup.conf settings applied to all tests:

  1. heap-size <value> - set separately for ip4, ip6, stats, main depending on scale tested.
  2. no-tx-checksum-offload - disables UDP / TCP TX checksum offload in DPDK. Typically needed for use faster vector PMDs (together with no-multi-seg).
  3. socket-mem <value>,<value> - memory per numa. (Not required anymore due to VPP code changes, will be removed in CSIT-19.04.)

Per Test Settings

List of vpp startup.conf settings applied dynamically per test:

  1. corelist-workers <list_of_cores> - list of logical cores to run VPP worker data plane threads. Depends on HyperThreading and core per test configuration.
  2. num-rx-queues <value> - depends on a number of VPP threads and NIC interfaces.
  3. num-rx-desc/num-tx-desc - number of rx/tx descriptors for specific NICs, incl. xl710, x710, xxv710.
  4. num-mbufs <value> - increases number of buffers allocated, needed only in scenarios with large number of interfaces and worker threads. Value is per CPU socket. Default is 16384.
  5. no-multi-seg - disables multi-segment buffers in DPDK, improves packet throughput, but disables Jumbo MTU support. Disabled for all tests apart from the ones that require Jumbo 9000B frame support.
  6. UIO driver - depends on topology file definition.
  7. QAT VFs - depends on NRThreads, each thread = 1QAT VFs.