I'm doing load testing with locust to see if my server can handle 1500 users.

What I'm using: Django, Nginx, Gunicorn, Postgresql My droplet: 24vCPUs, 128GB RAM, 25GB SSD

at about 1100 users I start getting the following errors in locust:

GET / HTTPError('502 Server Error: Bad Gateway for url: myurl.here ') GET /aboutpage/ HTTPError('502 Server Error: Bad Gateway for url: myurl.here ')

In my nginx error.log I get the following errors:

2020/01/26 23:14:17 [error] 30465#30465: *167765 connect() to unix:/var/www/file/to/sock/gunicorn failed (11: Resource temporarily unavailable) while connecting to upstream, client: 8x.8x.1xx.3x, server: mysite.here, request: "GET // HTTP/1.1", upstream: "http://unix:/var/www/file/to/sock/gunicorn://", host: "mysite.here"

for some reason it tells me that my Resource is temporarily unavailable.

Here is my nginx.conf:

user www-data; worker_processes auto; pid /run/nginx.pid; include /etc/nginx/modules-enabled/*.conf; events { worker_connections 2048; # multi_accept on; } http { ## # Basic Settings ## sendfile on; tcp_nopush on; tcp_nodelay on; keepalive_timeout 65; types_hash_max_size 2048; # server_tokens off; # server_names_hash_bucket_size 64; # server_name_in_redirect off; include /etc/nginx/mime.types; default_type application/octet-stream; ## # SSL Settings ## ssl_protocols TLSv1 TLSv1.1 TLSv1.2; # Dropping SSLv3, ref: POODLE ssl_prefer_server_ciphers on; ## # Logging Settings ## access_log /var/log/nginx/access.log; error_log /var/log/nginx/error.log; ## # Gzip Settings ## gzip on; # gzip_vary on; # gzip_proxied any; # gzip_comp_level 6; # gzip_buffers 16 8k; # gzip_http_version 1.1; # gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript; # Virtual Host Configs include /etc/nginx/conf.d/*.conf; include /etc/nginx/sites-enabled/*; }

And here is my server block configuration:

upstream mysite-production { server unix:/var/www/path/to/sock/gunicorn; } server { listen [::]:80; listen 80; server_name mysite.here; # set client body size to 100M # client_max_body_size 100M; location / { include proxy_params; proxy_pass http://unix:/var/www/path/to/sock/gunicorn; auth_basic "Restricted Content"; auth_basic_user_file /etc/nginx/.htpasswd; } location /static/ { root /var/www/site/production/; expires 30d; add_header Vary Accept-Encoding; access_log off; gzip on; gzip_comp_level 6; gzip_vary on; gzip_types text/plain text/css application/json application/x-javascript application/javascript text/xml application/xml application/rss+xml text/javascript image/svg+xml application/vnd.ms-fontobject application/x-font-ttf font/opentype; } location /media/ { root /var/www/site/production/; expires 30d; add_header Vary Accept-Encoding; access_log off; } }

Here is my gunicorn service file:

[Unit] Description=mysite production daemon After=network.target [Service] User=www-data Group=www-data WorkingDirectory=/var/www/path/to/site/src ExecStart=/var/www/path/to/venv/bin/gunicorn --workers=49 --bind unix:/var/www/path/to/sock/gunicorn --log-level DEBUG --log-file '/var/www/path/to/log/gunicorn.log' mysite.wsgi:application ExecReload=/bin/kill -s HUP $MAINPID ExecStop=/bin/kill -s TERM $MAINPID [Install] WantedBy=multi-user.target

What could be causing this problem? We are predicting about 1500-2000 concurrent users that will be on the site at the same time.

Thank you for taking the time! I'm looking forward to your answers!