➜  /  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
100%  200746 (longest request)