Question

I am working on a Node.js workload test and I have just encountered an interesting behavior. The minimum response time of an HTTP server is 200 ms, even for simplest logic:

var http = require("http");

http.createServer(function(request, response) { 

  response.write("Hello World");
  response.end();

}).listen(8080);

Ran on Windows Server 2003:

> node main.js

I searched the web, but have not found any information about this. The test is done on local network, furthermore with the use of other webserver (namely IIS) I can achieve instant response time. Don’t get me wrong, I see rational explanation behind this behavior, so this is my question:

Is this the default behavior coming with node.js, or could it be the result of something else?

Clarification on demand:

• Node js version: 0.6.11
• OS: Windows Server 2003 R2 SP2
• Server environment: VMWare Workstation 8.0.0
• Workload utility: jMeter 2.6 (1 thread workload)

Update

The delay behavior only appear during remote requests. If a local workload test is executed, the latency will be close to zero. However, it cannot be a network latency issue, because a remote request against IIS on the same server does not give latency. I am going to try this out on other OSes.

Answer 1

It is Nagle algorithm set by default on Windows (reproducible also on Windows 2008 R2 on Azure).

Workaround – disable it on response socket, like this:

response.connection.setNoDelay(true);