同步和异步代码
　　class SyncSleepHandler(RequestHandler):
　　"""
　　同步的方式，一个延时1s的接口
　　"""
　　def get(self):
　　time.sleep(1)
　　self.write("when i sleep 5s")
　　class SleepHandler(RequestHandler):
　　"""
　　异步的延时1秒的接口
　　"""
　　@tornado.gen.coroutine
　　def get(self):
　　yield tornado.gen.Task(
　　tornado.ioloop.IOLoop.instance().add_timeout，
　　time.time() + 1
　　)
　　self.write("when i sleep 5s")
　　同步测试结果
　　?  /  ab -n 200 -c 40 http://localhost:8009/demo/syncsleep-handler/
　　This is ApacheBench， Version 2.3 <$Revision: 1528965 $>
　　Copyright 1996 Adam Twiss， Zeus Technology Ltd， http://www.zeustech.net/
　　Licensed to The Apache Software Foundation， http://www.apache.org/
　　Benchmarking localhost (be patient)
　　Completed 100 requests
　　Completed 200 requests
　　Finished 200 requests
　　Server Software:        TornadoServer/4.2.1
　　Server Hostname:        localhost
　　Server Port:            8009
　　Document Path:          /demo/syncsleep-handler/
　　Document Length:        15 bytes
　　Concurrency Level:      40
　　Time taken for tests:   200.746 seconds
　　Complete requests:      200
　　Failed requests:        0
　　Total transferred:      42000 bytes
　　HTML transferred:       3000 bytes
　　Requests per second:    1.00 [#/sec] (mean)
　　Time per request:       40149.159 [ms] (mean)
　　Time per request:       1003.729 [ms] (mean， across all concurrent requests)
　　Transfer rate:          0.20 [Kbytes/sec] received
　　Connection Times (ms)
　　min  mean[+/-sd] median   max
　　Connect:        0    0   0.2      0       1
　　Processing:  1005 36235 18692.2  38133  200745
　　Waiting:     1005 36234 18692.2  38133  200745
　　Total:       1006 36235 18692.2  38133  200746
　　Percentage of the requests served within a certain time (ms)
　　50%  38133
　　66%  38137
　　75%  38142
　　80%  38161
　　90%  38171
　　95%  38176
　　98%  38179
　　99%  199742
　　  200746 (longest request)
　　异步测试结果
　　?  /  ab -n 200 -c 40 http://localhost:8009/demo/sleep-handler/
　　This is ApacheBench， Version 2.3 <$Revision: 1528965 $>
　　Copyright 1996 Adam Twiss， Zeus Technology Ltd， http://www.zeustech.net/
　　Licensed to The Apache Software Foundation， http://www.apache.org/
　　Benchmarking localhost (be patient)
　　Completed 100 requests
　　Completed 200 requests
　　Finished 200 requests
　　Server Software:        TornadoServer/4.2.1
　　Server Hostname:        localhost
　　Server Port:            8009
　　Document Path:          /demo/sleep-handler/
　　Document Length:        15 bytes
　　Concurrency Level:      40
　　Time taken for tests:   5.083 seconds
　　Complete requests:      200
　　Failed requests:        0
　　Total transferred:      42000 bytes
　　HTML transferred:       3000 bytes
　　Requests per second:    39.35 [#/sec] (mean)
　　Time per request:       1016.611 [ms] (mean)
　　Time per request:       25.415 [ms] (mean， across all concurrent requests)
　　Transfer rate:          8.07 [Kbytes/sec] received
　　Connection Times (ms)
　　min  mean[+/-sd] median   max
　　Connect:        0    0   0.4      0       2
　　Processing:  1001 1010  12.0   1005    1053
　　Waiting:     1001 1010  12.0   1005    1053
　　Total:       1001 1010  12.3   1005    1055
　　Percentage of the requests served within a certain time (ms)
　　50%   1005
　　66%   1009
　　75%   1011
　　80%   1015
　　90%   1032
　　95%   1044
　　98%   1045
　　99%   1054
　　   1055 (longest request)