hello_world_web_server.js

// A simple web server

var http = require("http"), server;

server = http.createServer(function (request, response) {
    response.writeHead(200, {
        "Content-Type": "text/plain"
    });

    response.write("Hello World\n");
    response.end();
}).listen(80);

incr_web_server.js

// A simple web server that generates dynamic content
//   based on responses from Redis

var host = '192.168.1.120',
    http = require("http"), server,
    redis_client = require("redis").createClient(6379, host);

server = http.createServer(function (request, response) {
    response.writeHead(200, {
        "Content-Type": "text/plain"
    });
    
    redis_client.incr("requests", function (err, reply) {
        response.write("requests: " + reply + "\n");
        response.end();
    });
}).listen(80);

test_node_conc.sh

#!/bin/bash

THRESH_SLEEP=5

RQ_NUM=100000
HOST="192.168.1.157"
PORT=80

function conc_node_reqs() {
  T=0
  if [ -n "$1" ]; then
    T=$1
  fi
  while [ $C -lt $MAXC ]; do
     if [ $T -gt 0 ]; then
       while true; do
         THRESH=$(wc -l /proc/net/tcp |cut -f 1 -d \/)
         if [ $THRESH -le $T ]; then break; fi;
         echo "    Sleep $THRESH_SLEEP: THRESHOLD: $T is not yet met $THRESH";
         sleep $THRESH_SLEEP
       done
    fi
    echo -ne "$C: ";
    taskset -c 1 ab -n $RQ_NUM -c $C -k http://${HOST}:${PORT}/ 2>/dev/null |grep "Requests per second:"
     C=$[${C}+${CDELTA}];
  done
}

MAXC=20;
C=1;
CDELTA=1
conc_node_reqs

C=20
MAXC=200;
CDELTA=20
conc_node_reqs

C=200
MAXC=4000;
CDELTA=100
conc_node_reqs 2000

C=4000
MAXC=20000;
CDELTA=2000
conc_node_reqs 2000