Run distributed load testing based on GCP and vegeta

vegeta.sh

#!/bin/bash
# Usage: bash vegeta.sh <rate> <duration>

ACTION="GET http://google.com"
DURATION=${2:-5s}
RATE=${1:-10}
SLAVE_INSTANCES=$(gcloud compute instances list | grep vegeta- | awk '{print $1}')
SSH_ARGS="-o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null"

# --- run cmd on all slave instances in parallel ---
SLAVE_INSTANCES_STR=$(echo "$SLAVE_INSTANCES" | paste -sd "," -)
echo Run on $SLAVE_INSTANCES_STR

SSH_CMD="echo ${ACTION} | vegeta attack -rate=${RATE} -duration=${DURATION} \
    -timeout=3s -workers=${RATE} > result.bin"
PDSH_SSH_ARGS_APPEND="-q ${SSH_ARGS}" \
    pdsh -R ssh -b -w ${SLAVE_INSTANCES_STR} ${SSH_CMD}

# --- collect results ---
SLAVE_INSTANCES_STR=$(echo "$SLAVE_INSTANCES" | paste -sd ";" -)
IFS=';' read -r -a MACHINES <<< "$SLAVE_INSTANCES_STR"

for m in "${MACHINES[@]}"
do
    echo fetch from ${m}
    scp -q ${SSH_ARGS} ${m}:~/result.bin ${m}.bin &
done
wait

# --- report ---
RESULT_BINS=$(ls -l | grep vegeta- | awk '{print $NF}' | paste -sd "," -)
vegeta report -inputs="${RESULT_BINS}"

# --- clean ---
rm -rf *.bin