nodejs response speed and nginx

Question

Just started testing nodejs, and wanted to get some help in understanding following behavior:

Example #1:

var http = require(\'http\');
http.create         


        

Answer 1

Peeking into http.js reveals that case #1 has special handling in nodejs itself, some kind of a shortcut optimization I guess.

var hot = this._headerSent === false &&
            typeof(data) === 'string' &&
            data.length > 0 &&
            this.output.length === 0 &&
            this.connection &&
            this.connection.writable &&
            this.connection._httpMessage === this;

      if (hot) {
        // Hot path. They're doing
        //   res.writeHead();
        //   res.end(blah);
        // HACKY.

        if (this.chunkedEncoding) {
          var l = Buffer.byteLength(data, encoding).toString(16);
          ret = this.connection.write(this._header + l + CRLF +
                                      data + '\r\n0\r\n' +
                                      this._trailer + '\r\n', encoding);
        } else {
          ret = this.connection.write(this._header + data, encoding);
        }
        this._headerSent = true;

      } else if (data) {
        // Normal body write.
        ret = this.write(data, encoding);
      }

      if (!hot) {
        if (this.chunkedEncoding) {
          ret = this._send('0\r\n' + this._trailer + '\r\n'); // Last chunk.
        } else {
          // Force a flush, HACK.
          ret = this._send('');
        }
      }

      this.finished = true;

Answer 2

I've took you examples files and used ab (Apache Benchmark) as a proper tool for benchmarking HTTP server performance:

Example 1:

Concurrency Level:      50
Time taken for tests:   0.221 seconds
Complete requests:      1000
Failed requests:        0
Write errors:           0
Total transferred:      104000 bytes
HTML transferred:       3000 bytes
Requests per second:    4525.50 [#/sec] (mean)
Time per request:       11.049 [ms] (mean)
Time per request:       0.221 [ms] (mean, across all concurrent requests)
Transfer rate:          459.62 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.7      0       4
Processing:     1   11   6.4     10      32
Waiting:        1   11   6.4     10      32
Total:          1   11   6.7     10      33

Example 2:

Concurrency Level:      50
Time taken for tests:   0.256 seconds
Complete requests:      1000
Failed requests:        0
Write errors:           0
Total transferred:      107000 bytes
HTML transferred:       6000 bytes
Requests per second:    3905.27 [#/sec] (mean)
Time per request:       12.803 [ms] (mean)
Time per request:       0.256 [ms] (mean, across all concurrent requests)
Transfer rate:          408.07 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.6      0       4
Processing:     1   12   7.0     12      34
Waiting:        1   12   6.9     12      34
Total:          1   12   7.1     12      34

Note:

The second example is as fast as the first one. The small differences are probably caused by the the additional function call in the code and the fact that the document size is larger then with the first one.