benchmark: support for multiple http benchmarkers

This adds support for multiple HTTP benchmarkers. Adds autocannon
as the secondary benchmarker.

PR-URL: https://github.com/nodejs/node/pull/8140
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

7 files changed, 242 insertions, 65 deletions

diff --git a/benchmark/README.md b/benchmark/README.md
index 225236cc10..770df01837 100644
--- a/benchmark/README.md
+++ b/benchmark/README.md
@@ -14,9 +14,25 @@ This folder contains benchmarks to measure the performance of the Node.js APIs.
 
 ## Prerequisites
 
-Most of the http benchmarks require [`wrk`][wrk] to be installed. It may be
-available through your preferred package manager. If not, `wrk` can be built
-[from source][wrk] via `make`.
+Most of the HTTP benchmarks require a benchmarker to be installed, this can be
+either [`wrk`][wrk] or [`autocannon`][autocannon].
+
+`Autocannon` is a Node script that can be installed using
+`npm install -g autocannon`. It will use the Node executable that is in the
+path, hence if you want to compare two HTTP benchmark runs make sure that the
+Node version in the path is not altered.
+
+`wrk` may be available through your preferred package manger. If not, you can
+easily build it [from source][wrk] via `make`.
+
+By default `wrk` will be used as benchmarker. If it is not available
+`autocannon` will be used in it its place. When creating a HTTP benchmark you
+can specify which benchmarker should be used. You can force a specific
+benchmarker to be used by providing it as an argument, e. g.:
+
+`node benchmark/run.js --set benchmarker=autocannon http`
+
+`node benchmark/http/simple.js benchmarker=autocannon`
 
 To analyze the results `R` should be installed. Check you package manager or
 download it from https://www.r-project.org/.
@@ -287,5 +303,48 @@ function main(conf) {
 }
 ```
 
+## Creating HTTP benchmark
+
+The `bench` object returned by `createBenchmark` implements
+`http(options, callback)` method. It can be used to run external tool to
+benchmark HTTP servers.
+
+```js
+'use strict';
+
+const common = require('../common.js');
+
+const bench = common.createBenchmark(main, {
+  kb: [64, 128, 256, 1024],
+  connections: [100, 500]
+});
+
+function main(conf) {
+  const http = require('http');
+  const len = conf.kb * 1024;
+  const chunk = Buffer.alloc(len, 'x'); 
+  const server = http.createServer(function(req, res) {
+    res.end(chunk);
+  });
+
+  server.listen(common.PORT, function() {
+    bench.http({
+      connections: conf.connections,
+    }, function() {
+      server.close();
+    });
+  });
+}
+```
+
+Supported options keys are:
+* `port` - defaults to `common.PORT`
+* `path` - defaults to `/`
+* `connections` - number of concurrent connections to use, defaults to 100
+* `duration` - duration of the benchmark in seconds, defaults to 10
+* `benchmarker` - benchmarker to use, defaults to
+`common.default_http_benchmarker`
+
+[autocannon]: https://github.com/mcollina/autocannon
 [wrk]: https://github.com/wg/wrk
 [t-test]: https://en.wikipedia.org/wiki/Student%27s_t-test#Equal_or_unequal_sample_sizes.2C_unequal_variances
diff --git a/benchmark/_http-benchmarkers.js b/benchmark/_http-benchmarkers.js
new file mode 100644
index 0000000000..ca8b462506
--- /dev/null
+++ b/benchmark/_http-benchmarkers.js
@@ -0,0 +1,130 @@
+'use strict';
+
+const child_process = require('child_process');
+
+// The port used by servers and wrk
+exports.PORT = process.env.PORT || 12346;
+
+function AutocannonBenchmarker() {
+  this.name = 'autocannon';
+  this.autocannon_exe = process.platform === 'win32'
+                      ? 'autocannon.cmd'
+                      : 'autocannon';
+  const result = child_process.spawnSync(this.autocannon_exe, ['-h']);
+  this.present = !(result.error && result.error.code === 'ENOENT');
+}
+
+AutocannonBenchmarker.prototype.create = function(options) {
+  const args = ['-d', options.duration, '-c', options.connections, '-j', '-n',
+                `http://127.0.0.1:${options.port}${options.path}` ];
+  const child = child_process.spawn(this.autocannon_exe, args);
+  return child;
+};
+
+AutocannonBenchmarker.prototype.processResults = function(output) {
+  let result;
+  try {
+    result = JSON.parse(output);
+  } catch (err) {
+    // Do nothing, let next line handle this
+  }
+  if (!result || !result.requests || !result.requests.average) {
+    return undefined;
+  } else {
+    return result.requests.average;
+  }
+};
+
+function WrkBenchmarker() {
+  this.name = 'wrk';
+  this.regexp = /Requests\/sec:[ \t]+([0-9\.]+)/;
+  const result = child_process.spawnSync('wrk', ['-h']);
+  this.present = !(result.error && result.error.code === 'ENOENT');
+}
+
+WrkBenchmarker.prototype.create = function(options) {
+  const args = ['-d', options.duration, '-c', options.connections, '-t', 8,
+                `http://127.0.0.1:${options.port}${options.path}` ];
+  const child = child_process.spawn('wrk', args);
+  return child;
+};
+
+WrkBenchmarker.prototype.processResults = function(output) {
+  const match = output.match(this.regexp);
+  const result = match && +match[1];
+  if (!result) {
+    return undefined;
+  } else {
+    return result;
+  }
+};
+
+const http_benchmarkers = [ new WrkBenchmarker(),
+                            new AutocannonBenchmarker() ];
+
+const benchmarkers = {};
+
+http_benchmarkers.forEach((benchmarker) => {
+  benchmarkers[benchmarker.name] = benchmarker;
+  if (!exports.default_http_benchmarker && benchmarker.present) {
+    exports.default_http_benchmarker = benchmarker.name;
+  }
+});
+
+exports.run = function(options, callback) {
+  options = Object.assign({
+    port: exports.PORT,
+    path: '/',
+    connections: 100,
+    duration: 10,
+    benchmarker: exports.default_http_benchmarker
+  }, options);
+  if (!options.benchmarker) {
+    callback(new Error('Could not locate any of the required http ' +
+                       'benchmarkers. Check benchmark/README.md for further ' +
+                       'instructions.'));
+    return;
+  }
+  const benchmarker = benchmarkers[options.benchmarker];
+  if (!benchmarker) {
+    callback(new Error(`Requested benchmarker '${options.benchmarker}' is ` +
+                       'not supported'));
+    return;
+  }
+  if (!benchmarker.present) {
+    callback(new Error(`Requested benchmarker '${options.benchmarker}' is ` +
+                       'not installed'));
+    return;
+  }
+
+  const benchmarker_start = process.hrtime();
+
+  const child = benchmarker.create(options);
+
+  child.stderr.pipe(process.stderr);
+
+  let stdout = '';
+  child.stdout.on('data', (chunk) => stdout += chunk.toString());
+
+  child.once('close', function(code) {
+    const elapsed = process.hrtime(benchmarker_start);
+    if (code) {
+      let error_message = `${options.benchmarker} failed with ${code}.`;
+      if (stdout !== '') {
+        error_message += ` Output: ${stdout}`;
+      }
+      callback(new Error(error_message), code);
+      return;
+    }
+
+    const result = benchmarker.processResults(stdout);
+    if (!result) {
+      callback(new Error(`${options.benchmarker} produced strange output: ` +
+                         stdout, code));
+      return;
+    }
+
+    callback(null, code, options.benchmarker, result, elapsed);
+  });
+
+};
diff --git a/benchmark/common.js b/benchmark/common.js
index 3807fea795..adc04a0b80 100644
--- a/benchmark/common.js
+++ b/benchmark/common.js
@@ -1,9 +1,7 @@
 'use strict';
 
 const child_process = require('child_process');
-
-// The port used by servers and wrk
-exports.PORT = process.env.PORT || 12346;
+const http_benchmarkers = require('./_http-benchmarkers.js');
 
 exports.createBenchmark = function(fn, options) {
   return new Benchmark(fn, options);
@@ -11,7 +9,9 @@ exports.createBenchmark = function(fn, options) {
 
 function Benchmark(fn, options) {
   this.name = require.main.filename.slice(__dirname.length + 1);
-  this.options = this._parseArgs(process.argv.slice(2), options);
+  const parsed_args = this._parseArgs(process.argv.slice(2), options);
+  this.options = parsed_args.cli;
+  this.extra_options = parsed_args.extra;
   this.queue = this._queue(this.options);
   this.config = this.queue[0];
 
@@ -29,7 +29,7 @@ function Benchmark(fn, options) {
 
 Benchmark.prototype._parseArgs = function(argv, options) {
   const cliOptions = Object.assign({}, options);
-
+  const extraOptions = {};
   // Parse configuration arguments
   for (const arg of argv) {
     const match = arg.match(/^(.+?)=([\s\S]*)$/);
@@ -38,14 +38,16 @@ Benchmark.prototype._parseArgs = function(argv, options) {
       process.exit(1);
     }
 
-    // Infer the type from the options object and parse accordingly
-    const isNumber = typeof options[match[1]][0] === 'number';
-    const value = isNumber ? +match[2] : match[2];
-
-    cliOptions[match[1]] = [value];
+    if (options[match[1]]) {
+      // Infer the type from the options object and parse accordingly
+      const isNumber = typeof options[match[1]][0] === 'number';
+      const value = isNumber ? +match[2] : match[2];
+      cliOptions[match[1]] = [value];
+    } else {
+      extraOptions[match[1]] = match[2];
+    }
   }
-
-  return cliOptions;
+  return { cli: cliOptions, extra: extraOptions };
 };
 
 Benchmark.prototype._queue = function(options) {
@@ -88,51 +90,29 @@ Benchmark.prototype._queue = function(options) {
   return queue;
 };
 
-function hasWrk() {
-  const result = child_process.spawnSync('wrk', ['-h']);
-  if (result.error && result.error.code === 'ENOENT') {
-    console.error('Couldn\'t locate `wrk` which is needed for running ' +
-      'benchmarks. Check benchmark/README.md for further instructions.');
-    process.exit(1);
-  }
-}
+// Benchmark an http server.
+exports.default_http_benchmarker =
+  http_benchmarkers.default_http_benchmarker;
+exports.PORT = http_benchmarkers.PORT;
 
-// benchmark an http server.
-const WRK_REGEXP = /Requests\/sec:[ \t]+([0-9\.]+)/;
-Benchmark.prototype.http = function(urlPath, args, cb) {
-  hasWrk();
+Benchmark.prototype.http = function(options, cb) {
   const self = this;
-
-  const urlFull = 'http://127.0.0.1:' + exports.PORT + urlPath;
-  args = args.concat(urlFull);
-
-  const childStart = process.hrtime();
-  const child = child_process.spawn('wrk', args);
-  child.stderr.pipe(process.stderr);
-
-  // Collect stdout
-  let stdout = '';
-  child.stdout.on('data', (chunk) => stdout += chunk.toString());
-
-  child.once('close', function(code) {
-    const elapsed = process.hrtime(childStart);
-    if (cb) cb(code);
-
-    if (code) {
-      console.error('wrk failed with ' + code);
-      process.exit(code);
+  const http_options = Object.assign({ }, options);
+  http_options.benchmarker = http_options.benchmarker ||
+                             self.config.benchmarker ||
+                             self.extra_options.benchmarker ||
+                             exports.default_http_benchmarker;
+  http_benchmarkers.run(http_options, function(error, code, used_benchmarker,
+                                               result, elapsed) {
+    if (cb) {
+      cb(code);
     }
-
-    // Extract requests pr second and check for odd results
-    const match = stdout.match(WRK_REGEXP);
-    if (!match || match.length <= 1) {
-      console.error('wrk produced strange output:');
-      console.error(stdout);
-      process.exit(1);
+    if (error) {
+      console.error(error);
+      process.exit(code || 1);
     }
-
-    // Report rate
-    self.report(+match[1], elapsed);
+    self.config.benchmarker = used_benchmarker;
+    self.report(result, elapsed);
   });
 };
 
@@ -152,6 +132,9 @@ Benchmark.prototype._run = function() {
     for (const key of Object.keys(config)) {
       childArgs.push(`${key}=${config[key]}`);
     }
+    for (const key of Object.keys(self.extra_options)) {
+      childArgs.push(`${key}=${self.extra_options[key]}`);
+    }
 
     const child = child_process.fork(require.main.filename, childArgs, {
       env: childEnv
diff --git a/benchmark/http/chunked.js b/benchmark/http/chunked.js
index a61978c732..46d6ab2e26 100644
--- a/benchmark/http/chunked.js
+++ b/benchmark/http/chunked.js
@@ -20,8 +20,6 @@ function main(conf) {
   const http = require('http');
   var chunk = Buffer.alloc(conf.size, '8');
 
-  var args = ['-d', '10s', '-t', 8, '-c', conf.c];
-
   var server = http.createServer(function(req, res) {
     function send(left) {
       if (left === 0) return res.end();
@@ -34,7 +32,9 @@ function main(conf) {
   });
 
   server.listen(common.PORT, function() {
-    bench.http('/', args, function() {
+    bench.http({
+      connections: conf.c
+    }, function() {
       server.close();
     });
   });
diff --git a/benchmark/http/cluster.js b/benchmark/http/cluster.js
index 95e76e69cc..732a5fad66 100644
--- a/benchmark/http/cluster.js
+++ b/benchmark/http/cluster.js
@@ -27,9 +27,11 @@ function main(conf) {
 
     setTimeout(function() {
       var path = '/' + conf.type + '/' + conf.length;
-      var args = ['-d', '10s', '-t', 8, '-c', conf.c];
 
-      bench.http(path, args, function() {
+      bench.http({
+        path: path,
+        connections: conf.c
+      }, function() {
         w1.destroy();
         w2.destroy();
       });
diff --git a/benchmark/http/end-vs-write-end.js b/benchmark/http/end-vs-write-end.js
index 0cdc88111d..62b1a6a097 100644
--- a/benchmark/http/end-vs-write-end.js
+++ b/benchmark/http/end-vs-write-end.js
@@ -43,14 +43,15 @@ function main(conf) {
   }
 
   var method = conf.method === 'write' ? write : end;
-  var args = ['-d', '10s', '-t', 8, '-c', conf.c];
 
   var server = http.createServer(function(req, res) {
     method(res);
   });
 
   server.listen(common.PORT, function() {
-    bench.http('/', args, function() {
+    bench.http({
+      connections: conf.c
+    }, function() {
       server.close();
     });
   });
diff --git a/benchmark/http/simple.js b/benchmark/http/simple.js
index eedda8e98f..66113ed375 100644
--- a/benchmark/http/simple.js
+++ b/benchmark/http/simple.js
@@ -15,9 +15,11 @@ function main(conf) {
   var server = require('./_http_simple.js');
   setTimeout(function() {
     var path = '/' + conf.type + '/' + conf.length + '/' + conf.chunks;
-    var args = ['-d', '10s', '-t', 8, '-c', conf.c];
 
-    bench.http(path, args, function() {
+    bench.http({
+      path: path,
+      connections: conf.c
+    }, function() {
       server.close();
     });
   }, 2000);