如何使用群集提高NodeJS服务器的吞吐量？

Question

我有一个NodeJS服务器(Express),我正在使用nodeJs站点上的集群模块示例将请求传播到多个处理器.

if (cluster.isMaster) {
  for (var i = 0; i < numCPUs; i++) {
    cluster.fork();
  };
  cluster.on('exit', function(worker, code, signal) {
    console.log('worker ' + worker.process.pid + ' died');
    cluster.fork();
  });
} else {  
  server.listen(app.get('port'), function(){
    console.log('HTTP server on port ' + app.get('port') + ' - running as ' + app.settings.env);
  });

  // setup socket.io communication
  io.sockets.on('connection', require('./app/sockets'));
  io.sockets.on('connection', require('./app/downloadSockets'));
}

问题在于围攻的基准测试表明,命中数没有增加.这是围攻的输出:

$ siege -c100 192.168.111.1:42424  -t10S
** SIEGE 3.0.5
** Preparing 100 concurrent users for battle.
The server is now under siege...
Lifting the server siege...      done.

Transactions:               1892 hits
Availability:             100.00 %
Elapsed time:              10.01 secs
Data transferred:           9.36 MB
Response time:              0.01 secs
Transaction rate:         189.01 trans/sec
Throughput:             0.93 MB/sec
Concurrency:                1.58
Successful transactions:        1892
Failed transactions:               0
Longest transaction:            0.05
Shortest transaction:           0.00

聚类后​​:

$ siege -c100 192.168.111.1:42424  -t10S
** SIEGE 3.0.5
** Preparing 100 concurrent users for battle.
The server is now under siege...
Lifting the server siege...      done.

Transactions:               1884 hits
Availability:             100.00 %
Elapsed time:               9.52 secs
Data transferred:           9.32 MB
Response time:              0.01 secs
Transaction rate:         197.90 trans/sec
Throughput:             0.98 MB/sec
Concurrency:                1.72
Successful transactions:        1884
Failed transactions:               0
Longest transaction:            0.07
Shortest transaction:           0.00

这是否意味着我的服务器已经获得单个服务器的最大吞吐量,可能是因为它是一台本地机器,或者由于运行的进程太多而无法获得4个处理器,我不确定.

如何使用群集模块来增加throghput以及为什么我当前的代码没有成功？此外,我检查它确实创建了服务器的4个实例,即cluster.fork工作.任何提示都非常有用.

Answer 1

通过聚类或增长并发查询来实现这种效果(尝试将并发用户数增加到300-400).或者造成严重负担的任务.让我们花更多有趣的测试:将下载大约1 MB的文件大小,另外我们会延迟5毫秒和50毫秒来模拟复杂的操作.对于本地测试的四核处理器将如下(分别为普通和集群):

$ siege -c100 http://localhost/images/image.jpg  -t10S

正常模式(5毫秒延迟):

Lifting the server siege...      done.
Transactions:                    1170 hits
Availability:                 100.00 %
Elapsed time:                   9.10 secs
Data transferred:             800.79 MB
Response time:                  0.27 secs
Transaction rate:             128.57 trans/sec
Throughput:                    88.00 MB/sec
Concurrency:                   34.84
Successful transactions:        1170
Failed transactions:               0
Longest transaction:            0.95
Shortest transaction:           0.01

群集模式(5毫秒延迟):

Lifting the server siege...      done.
Transactions:                    1596 hits
Availability:                 100.00 %
Elapsed time:                   9.04 secs
Data transferred:            1092.36 MB
Response time:                  0.06 secs
Transaction rate:             176.55 trans/sec
Throughput:                   120.84 MB/sec
Concurrency:                    9.81
Successful transactions:        1596
Failed transactions:               0
Longest transaction:            0.33
Shortest transaction:           0.00

正常模式(50毫秒延迟):

Lifting the server siege...      done.
Transactions:                     100 hits
Availability:                 100.00 %
Elapsed time:                   9.63 secs
Data transferred:              68.44 MB
Response time:                  5.51 secs
Transaction rate:              10.38 trans/sec
Throughput:                     7.11 MB/sec
Concurrency:                   57.18
Successful transactions:         100
Failed transactions:               0
Longest transaction:            7.77
Shortest transaction:           5.14

群集模式(50毫秒延迟):

Lifting the server siege...      done.
Transactions:                     614 hits
Availability:                 100.00 %
Elapsed time:                   9.24 secs
Data transferred:             420.25 MB
Response time:                  0.90 secs
Transaction rate:              66.45 trans/sec
Throughput:                    45.48 MB/sec
Concurrency:                   59.59
Successful transactions:         614
Failed transactions:               0
Longest transaction:            1.50
Shortest transaction:           0.50