(return to home)

Python and Node performance tests

This is another benchmark for view performance of python on the web. The main idea is to see python3 performance compared to python2 serving simple wsgi app.

Also compared with nodejs performance, performing the same task.

For benchmarks are used these software:

  • uwsgi-1.4.5 + python-3.3.0
  • uwsgi-1.4.5 + python-2.7.3
  • gunicorn-0.17.2 + python-3.3.0
  • gunicorn-0.17.2 + python-2.7.3
  • nodejs-v0.8.19 + v8-

Setup environment

This is a script used on python benchmarks:

from __future__ import unicode_literals

def u(data):
    return data.encode("utf-8")

def common_response():
    for x in range(100):
        yield u("text:item:{0}".format(x*2))

    data = []
    for item in range(100):
        if item % 2 == 0:
            for subitem in range(item):

    yield u("\n".join(data))

def application_py2(environ, start_response):
    start_response(b'200 OK', [(b'Content-Type', b'text/plain')])
    return common_response()

def application_py3(environ, start_response):
    start_response('200 OK', [('Content-Type', 'text/plain')])
    return common_response()

And this is a code used with nodejs:

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

    for(var i=0; i<100; i++) {
        response.write("text:item:" + i);

    var data = [];
    for(var i=0; i<100; i++) {
        if (i % 2 == 0) {
            data.push("other:item." + i)
        } else {
            for(var x=0; x<i; x++) {
                data.push("other:subitem." + x)



Server setup

There are a list of a commands used to start wsgi and nodejs servers.

Gunicorn + Python3

gunicorn -b -w1 app:application_py3

Gunicorn + Python2

gunicorn -b -w1 app:application_py2

uWsgi + Python3

uwsgi-py3 --http --master -p 1 -w app:application_py3 -L

uWsgi + Python2

uwsgi --http --master -p 1 -w app:application_py2 -L


node app.js


For measure the performance, I used apache bench tool (ab) and httperf, with 1, 5 and 10 concurrent clients making 1000 requests with keep-alive enabled.

Note: The results are average of multiple executions.

Req/s performance

Server 1 client 5 clients 10 clients
uWsgi+python3 235/s 315/s 323/s
uWsgi+python2 155/s 185/s 186/s
gunicorn+python3 137/s 137/s 137/s
gunicorn+python2 130/s 135/s 135/s
nodejs 330/s 375/s 375/s


Server 1 client 5 clients 10 clients
uWsgi+python3 4ms 15ms 30ms
uWsgi+python2 6ms 27ms 50ms
gunicorn+python3 7ms 35ms 72ms
gunicorn+python2 8ms 36ms 73ms
nodejs 2ms 13ms 27ms

Note: Additionally I've tested both: uwsgi with python3 and nodejs with a more clients and its scales proportionally wery well, accepting same number requests per seconds and increasing a response latency without any errors (tests up to 400 concurrent clients).


What I really wanted to see here is if python3 is a viable option for web and deny all of the myths that python3 is slow.

With respect to the application server, uwsgi is clearly faster. I am sure that if testing it in a more powerful environment, could be on par with nodejs performance.

In these tests nodejs clearly has better performance, but as Guido says, performance is not always the most important.

I usually use gunicorn for its simplicity and simplicity. Gunicorn is not the fastest, but in my opinon, in real applications, there are other major bottlenecks to solve, before noting the bottleneck in wsgi server.