Trying to understand benchmarking results

[Bill Appleton]

Hi All,

I ran some benchmarks on our DreamFactory product running on NGINX using
Apache Benchmark

DreamFactory is a REST API platform, but from a server point of view it
should look more or less like a simple WordPress website

see the graphical results here:
www*.dreamfactory.com/publications/comparison.png
<http://dreamfactory.com/publications/comparison.png>*

the red lines show the average and maximum response time for 500 requests
at different levels of concurrency running on a "medium" aws server with 1
CPU

the blue lines show the average and maximum response time for 500 requests
at different levels of concurrency running on a "large" aws server with 2
CPUs

Does anyone know why at about 100 concurrent requests we start to see some
requests taking much longer to finish?

Is this too much work for the processor? The database is overloaded? There
is some server setting that limits concurrency?

I have also included one of the benchmark reports below, as you can see
most of the requests are handled promptly but about 5% are deferred and
take a much longer time....

Any help would be appreciated!


Thanks,

Bill Appleton
www.dreamfactory.com




Server Software:        nginx
Server Hostname:        next.cloud.dreamfactory.com
Server Port:            80
Document Length:        126 bytes

Concurrency Level:      200
Time taken for tests:   16.147 seconds
Complete requests:      500
Failed requests:        0
Non-2xx responses:      500
Total transferred:      298000 bytes
HTML transferred:       63000 bytes
Requests per second:    30.97 [#/sec] (mean)
Time per request:       6458.755 [ms] (mean)
Time per request:       32.294 [ms] (mean, across all concurrent requests)
Transfer rate:          18.02 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:       85  209 208.7     91     725
Processing:   146 3605 2629.2   3096   15633
Waiting:      145 3604 2629.2   3095   15633
Total:        243 3814 2725.4   3189   16143

Percentage of the requests served within a certain time (ms)
  50%   3189
  66%   3264
  75%   3831
  80%   4175
  90%   6766
  95%  10568
  98%  11114
  99%  16069
 100%  16143 (longest request)
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