Making Dockerized Flask server concurrent - api

Question

I have a Flask server that I'm running on AWS Fargate. My task has 2 vCPUs and 8 GB of memory. My server is only able to respond to one request at a time. If I run 2 API requests at the same, each that takes 7 seconds, the first request will take 7 seconds to return and the second will take 14 seconds to return.
This is my Docker file (using this repo):
FROM tiangolo/uwsgi-nginx-flask:python3.7
COPY ./requirements.txt requirements.txt
RUN pip3 install --no-cache-dir -r requirements.txt
RUN python3 -m spacy download en
RUN apt-get update
RUN apt-get install wkhtmltopdf -y
RUN apt-get install poppler-utils -y
RUN apt-get install xvfb -y
COPY ./ /app
I have the following config file:
[uwsgi]
module = main
callable = app
enable-threads = true
These are my logs when I start the server:
Checking for script in /app/prestart.sh
Running script /app/prestart.sh
Running inside /app/prestart.sh, you could add migrations to this file, e.g.:
#! /usr/bin/env bash
# Let the DB start
sleep 10;
# Run migrations
alembic upgrade head
/usr/lib/python2.7/dist-packages/supervisor/options.py:298: UserWarning: Supervisord is running as root and it is searching for its configuration file in default locations (including its current working directory); you probably want to specify a "-c" argument specifying an absolute path to a configuration file for improved security.
'Supervisord is running as root and it is searching '
2019-10-05 06:29:53,438 CRIT Supervisor running as root (no user in config file)
2019-10-05 06:29:53,438 INFO Included extra file "/etc/supervisor/conf.d/supervisord.conf" during parsing
2019-10-05 06:29:53,446 INFO RPC interface 'supervisor' initialized
2019-10-05 06:29:53,446 CRIT Server 'unix_http_server' running without any HTTP authentication checking
2019-10-05 06:29:53,446 INFO supervisord started with pid 1
2019-10-05 06:29:54,448 INFO spawned: 'nginx' with pid 9
2019-10-05 06:29:54,450 INFO spawned: 'uwsgi' with pid 10
[uWSGI] getting INI configuration from /app/uwsgi.ini
[uWSGI] getting INI configuration from /etc/uwsgi/uwsgi.ini
;uWSGI instance configuration
[uwsgi]
cheaper = 2
processes = 16
ini = /app/uwsgi.ini
module = main
callable = app
enable-threads = true
ini = /etc/uwsgi/uwsgi.ini
socket = /tmp/uwsgi.sock
chown-socket = nginx:nginx
chmod-socket = 664
hook-master-start = unix_signal:15 gracefully_kill_them_all
need-app = true
die-on-term = true
show-config = true
;end of configuration
*** Starting uWSGI 2.0.18 (64bit) on [Sat Oct 5 06:29:54 2019] ***
compiled with version: 6.3.0 20170516 on 09 August 2019 03:11:53
os: Linux-4.14.138-114.102.amzn2.x86_64 #1 SMP Thu Aug 15 15:29:58 UTC 2019
nodename: ip-10-0-1-217.ec2.internal
machine: x86_64
clock source: unix
pcre jit disabled
detected number of CPU cores: 2
current working directory: /app
detected binary path: /usr/local/bin/uwsgi
your memory page size is 4096 bytes
detected max file descriptor number: 1024
lock engine: pthread robust mutexes
thunder lock: disabled (you can enable it with --thunder-lock)
uwsgi socket 0 bound to UNIX address /tmp/uwsgi.sock fd 3
uWSGI running as root, you can use --uid/--gid/--chroot options
*** WARNING: you are running uWSGI as root !!! (use the --uid flag) ***
Python version: 3.7.4 (default, Jul 13 2019, 14:20:24) [GCC 6.3.0 20170516]
Python main interpreter initialized at 0x55e1e2b181a0
uWSGI running as root, you can use --uid/--gid/--chroot options
*** WARNING: you are running uWSGI as root !!! (use the --uid flag) ***
python threads support enabled
your server socket listen backlog is limited to 100 connections
your mercy for graceful operations on workers is 60 seconds
mapped 1239640 bytes (1210 KB) for 16 cores
*** Operational MODE: preforking ***
2019-10-05 06:29:55,483 INFO success: nginx entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2019-10-05 06:29:55,484 INFO success: uwsgi entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)