pktgen: add sample script pktgen_sample03_burst_single_flow.sh

#!/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

[ -z "$DEST_IP" ]   && DEST_IP="198.18.0.42"

[ -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 $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"