# nginx file configured for Optimized Performance
# proudly by DevOps 90min ¯\_(ツ)_/¯

user  nginx nginx;
# auto - nginx will detect number of cpu and make ideal number of workers
worker_processes  auto;

# # [ debug | info | notice | warn | error | crit | alert | emerg ] 
error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;

# Changes the limit on the maximum number of open files (RLIMIT_NOFILE) for worker processes. 
# Used to increase the limit without restarting the main process.
worker_rlimit_nofile 8192;

# use epoll -  is a scalable I/O event notification mechanism to trigger on events and make sure that I/O is utilized to the best of its ability.
# multi_accept in order for a worker to accept all new connections at one time.
events {
    worker_connections 66536;
    use epoll;
    multi_accept on;
}

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;
    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 - optimizes serving static files from the file system, like logos.
    sendfile     on;
    # tcp_nopush - optimizes the amount of data sent down the wire at once by activating the TCP_CORK 
    # option within the TCP stack. TCP_CORK blocks the data until the packet reaches the MSS, 
    # which is equal to the MTU minus the 40 or 60 bytes of the IP header.
    tcp_nopush   on;
    # tcp_nodelay - allows nginx to make TCP send multiple buffers as individual packets.
    tcp_nodelay  on;  
    # keepalive_timeout and keepalive_requests control the keep alive settings.      
    keepalive_timeout      65;
    keepalive_requests     100000;

    # server_names_hash_max_size - Sets the maximum size of the server names hash tables.
    server_names_hash_max_size 512;

    # client_header_timeout - sends directives for the time a server will wait for a header body to be sent. 
    client_header_timeout  3m;
    # client_body_timeout - sends directives for the time a server will wait for a body to be sent.
    client_body_timeout    3m;
    # send_timeout - specifies the response timeout to the client. 
    send_timeout           3m;

    # client_header_buffer_size - handles the client header size.
    client_header_buffer_size 1k;
    # client_max_body_size - sets the max body buffer size.
    client_max_body_size 10m;
    # client_body_buffer_size - handles the client buffer size.
    client_body_buffer_size 128k;
    # large_client_header_buffers - shows the maximum number and size of buffers for large client headers. 
    large_client_header_buffers 4 4k;
    # output_buffers - sets the number and size of the buffers used for reading a response from a disk.
    output_buffers 1 32k;
    # postpone_output - client data will be postponed until nginx has at least size bytes of data to send. 
    postpone_output 1460;

    # gzip compression
    gzip on;
    gzip_disable "MSIE [1-6]\.";

    gzip_vary on;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_buffers 16 8k;
    gzip_http_version 1.1;
    gzip_min_length 1000;
    gzip_types text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript application/vnd.ms-fontobject application/x-font-ttf font/opentype image/svg+xml image/x-icon;
    
    include /etc/nginx/conf.d/*.conf;
}