uWSGI: limit memory usage - set max-fd

[thorkill]

In some circumstances uWSGI allocates over 8GB of RAM while using docker (latest).

detected max file descriptor number: 1073741816

Check your memory consumption:

$> docker top linkding -eo pid,cmd,size
PID                 CMD                 SIZE
1559667             uwsgi               --http [::]:9090 uwsg 41212
1559729             uwsgi               --http [::]:9090 uwsg 49552
1559731             uwsgi               --http [::]:9090 uwsg 49552
1559733             uwsgi               --http [::]:9090 uwsg 8429820

While investigating the issue I have came across:

unbit/uwsgi#2299

Following the lead I have limited max-df = 4096 in uwsgi.ini. The value is probably to low for larger instances however 1073741816 is too large.

The memory consumption is now "normal" without any issues (I am not using archive/snaptshot/chromium).

$> docker top linkding -eo pid,cmd,size
PID                 CMD                 SIZE
1582194             uWSGI               master 41276
1582294             uWSGI               worker 1 58788
1582296             uWSGI               worker 2 54956
1582298             uWSGI               http 1 41276

[thorkill]

Relates to #453