#!/bin/bash
#
# Script for max single flow performance
# - If correctly tuned[1], single CPU 10G wirespeed small pkts is possible[2]
#
# Using pktgen "burst" option (use -b $N)
# - To boost max performance
# - Avail since: kernel v3.18
# * commit 38b2cf2982dc73 ("net: pktgen: packet bursting via skb->xmit_more")
# - This avoids writing the HW tailptr on every driver xmit
# - The performance boost is impressive, see commit and blog [2]
#
# Notice: On purpose generates a single (UDP) flow towards target,
# reason behind this is to only overload/activate a single CPU on
# target host. And no randomness for pktgen also makes it faster.
#
# Tuning see:
# [1] http://netoptimizer.blogspot.dk/2014/06/pktgen-for-network-overload-testing.html
# [2] http://netoptimizer.blogspot.dk/2014/10/unlocked-10gbps-tx-wirespeed-smallest.html
#
basedir=`dirname $0`
source ${basedir}/functions.sh
root_check_run_with_sudo "$@"
# Parameter parsing via include
source ${basedir}/parameters.sh
# Set some default params, if they didn't get set
if [ -z "$DEST_IP" ]; then
[ -z "$IP6" ] && DEST_IP="198.18.0.42" || DEST_IP="FD00::1"
fi
[ -z "$DST_MAC" ] && DST_MAC="90:e2:ba:ff:ff:ff"
[ -z "$BURST" ] && BURST=32
[ -z "$CLONE_SKB" ] && CLONE_SKB="100000"
# Base Config
DELAY="0" # Zero means max speed
COUNT="0" # Zero means indefinitely
# General cleanup everything since last run
pg_ctrl "reset"
# Threads are specified with parameter -t value in $THREADS
for ((thread = 0; thread < $THREADS; thread++)); do
dev=${DEV}@${thread}
# Add remove all other devices and add_device $dev to thread
pg_thread $thread "rem_device_all"
pg_thread $thread "add_device" $dev
# Base config
pg_set $dev "flag QUEUE_MAP_CPU"
pg_set $dev "count $COUNT"
pg_set $dev "clone_skb $CLONE_SKB"
pg_set $dev "pkt_size $PKT_SIZE"
pg_set $dev "delay $DELAY"
pg_set $dev "flag NO_TIMESTAMP"
# Destination
pg_set $dev "dst_mac $DST_MAC"
pg_set $dev "dst$IP6 $DEST_IP"
# Setup burst, for easy testing -b 0 disable bursting
# (internally in pktgen default and minimum burst=1)
if [[ ${BURST} -ne 0 ]]; then
pg_set $dev "burst $BURST"
else
info "$dev: Not using burst"
fi
done
# Run if user hits control-c
function control_c() {
# Print results
for ((thread = 0; thread < $THREADS; thread++)); do
dev=${DEV}@${thread}
echo "Device: $dev"
cat /proc/net/pktgen/$dev | grep -A2 "Result:"
done
}
# trap keyboard interrupt (Ctrl-C)
trap control_c SIGINT
echo "Running... ctrl^C to stop" >&2
pg_ctrl "start"
e