502 bad gateway after 30 seconds - nginx

Question

One of the pages on my website requires a long computation on the server(~2 minutes). If I run the website on localhost it works fine. But in production when ~30 seconds. Here's my http section of the nginx conf:
http {
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
access_log /var/log/nginx/access.log main;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 120;
types_hash_max_size 2048;
include /etc/nginx/mime.types;
default_type application/octet-stream;
# Load modular configuration files from the /etc/nginx/conf.d directory.
# See http://nginx.org/en/docs/ngx_core_module.html#include
# for more information.
include /etc/nginx/conf.d/*.conf;
server {
listen 80 default_server;
listen [::]:80 default_server;
server_name _;
root /usr/share/nginx/html;
# Load configuration files for the default server block.
include /etc/nginx/default.d/*.conf;
location / {
proxy_read_timeout 300;
proxy_connect_timeout 300;
}
error_page 404 /404.html;
location = /40x.html {
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
}
}
I tried adding:
fastcgi_read_timeout 300;
proxy_read_timeout 300;
at the end(after "server") but it didn't do anything.

Answer 1

If you get 502 Bad Gateway error it means your Application server(i guess its Unicorn according to your tags) is sending the timeout and not Nginx, you should increase the timeout in your unicorn.rb file in your production server.
worker_processes 2
listen "/tmp/xxx.socket"
##equal to your proxy read timeout in the Nginx config.
timeout 300
pid "/tmp/unicorn.xxx.pid"
In case of Python Green Unicorn please do the following:
NUM_WORKERS=3
TIMEOUT=300
exec gunicorn ${DJANGO_WSGI_MODULE}:application \
--name $NAME \
--workers $NUM_WORKERS \
--timeout $TIMEOUT \
--log-level=debug \
--bind=x.x.x.x \
--pid=$PIDFILE