Moving from uwsgi to gunicorn

[Lucas-C]

Quick benchmark, testing the new Docker image on my computer:

$ pip install salvo
$ salvo http://localhost/metrics -c 4 -n 10
-------- Server info --------

Server Software: meinheld/1.0.2

-------- Running 10 queries - concurrency 4 --------

[=================================================================>] 100%

-------- Results --------

Successful calls                39
Total time                      1971.8814 s
Average                         50.5611 s
Fastest                         14.5381 s
Slowest                         58.9263 s
Amplitude                       44.3882 s
Standard deviation              9.051222
Requests Per Second             0.02
Requests Per Minute             1.19

-------- Status codes --------
Code 200                        39 times.

[Lucas-C]

Current stats when performing the same benchmark on the master version of Sonar-Exporter:

$ salvo http://localhost:9119/metrics -c 4 -n 10
-------- Server info --------

Server Software: Unknown

-------- Running 10 queries - concurrency 4 --------

[=================================================================>] 100%

-------- Results --------

Successful calls                40
Total time                      2142.7936 s
Average                         53.5698 s
Fastest                         14.1758 s
Slowest                         104.9278 s
Amplitude                       90.7520 s
Standard deviation              15.330761
Requests Per Second             0.02
Requests Per Minute             1.12

-------- Status codes --------
Code 200                        40 times.

So it does not make a major difference, but it seems we reduce the duration of the slowest queries