ANLAB-KAIST / pspgen-dpdk

pspgen utility on top of DPDK

pspgen-dpdk

The pspgen utility on top of DPDK

Overview

It is a port of pspgen in the psio examples. Our team uses pspgen as a packet generator and latency measurement tool in a daily basis, and now it works with DPDK as well. All functionalities are in a self-contained pspgen.c file which demonstrates a minimal code to use DPDK.

How to compile and run

Here is an example on a 8 core machine with three memory channels, which generates 64 bytes IPv4 packets randomly.

export RTE_TARGET=x86_64-native-linuxapp-gcc
export RTE_SDK=$HOME/dpdk/$RTE_TARGET
export PSPGEN_PMD=ixgbe
make
$EDITOR neighbors.conf
sudo ./pspgen -cff -n3 -- -i all -f 0 -v 4 -p 64

Differently from the psio version, it takes two disjoin sets of arguments: one set for DPDK EAL and the other set for pspgen itself, separated by --. To see detailed arguments, just run sudo ./pspgen. You may not need sudo depending on your system configuration (/dev/uioX and hugepage permissions). Change the EAL arguments according to your hardware.

Another difference is that the device names are no longer xge# but rte_ixgbe_pmd.# (a string composed of DPDK driver name, dot, and the enumeration index) instead because DPDK-managed interfaces does not have host-bound interface names.

neighbors.conf file should contain the destination MAC addresses one-to-one-mapped to the NIC ports used by pspgen-dpdk. (e.g., If you use 4 NIC ports to generate packets, then you need 4 destination MAC addresses.) The MAC addresses should be written in the standard colon-spearated six 2-digit hexademical numbers placed line-by-line. neighbors.conf should also specify the destination IP addresses at the end of each line, but currently they are not used and you may put 0.0.0.0 as placeholders. Each line looks like 01:23:45:67:89:ab 0.0.0.0.

Highlighted Features

• Latency measurement: use -l to show average latency and --latency-record-prefix to get histograms (0 to 10 msec in microsecond accuracy)
• Rate limiting: use -g to specify total offered throughput by the generator in Gbps (including ethernet overheads). If the DPDK driver supports, it uses hardware rate limiter. Otherwise, it falls back to software rate limiter. (Note that activating latency measurement always falls back to software rate limiter to exclude delays inserted by the hardware, which is not accessible from the software.)

Future Work (pull requests are welcome!)

• Hardware timestamping for latency measurement (e.g., for Mellanox cards)
• More generalized random packet generation. (Maybe scriptable?)
• TCP flow generation
• A daemon to run experiments faster