I wonder how I could improve the performance of my server? It is configured with Ubuntu 18.04 (LTS), 4 GB RAM, 100 GB SSD, 2 CPU, with Nginx 1.14.0 and PHP 7.2-fpm to handle running and serving a site that generates dynamic pages from a database. PHP has OP cache enabled. I would like to improve current setup without Varnish or proxy, just a plain Nginx with PHP setup.
Monitoring when load testing with 500 concurrent visitors, it reveals that CPU usage immediately jumps to 100% with PHP using the majority, 65% and SQL 15%. Memory usage is about 2,5Gb with 0,75Gb free and the swapfile untouched. When visiting the site during the test, there are 502 errors.
The logs, php7.2-fpm.log:
[12-May-2020 17:21:13] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 8 children, there are 0 idle, and 9 total children [12-May-2020 17:21:14] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 16 children, there are 0 idle, and 10 total children [12-May-2020 17:21:15] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 0 idle, and 11 total childr And in /var/log/nginx/error.log
2020/05/12 17:22:35 [error] 2936#2936: *25711 connect() to unix:/var/run/php/php7.2-fpm.sock failed (11: Resource temporarily unavailable) while connecting to upstream, client: [IPADDRESS], server: [DOMAINNAME], request: "GET /[URL] HTTP/1.1", upstream: "fastcgi://unix:/var/run/php/php7.2-fpm.sock:", host: "[HOSTNAME]" Below are the configurations of Nginx and PHP
relevant settings in /etc/php/7.2/fpm/pool.d/www.conf:
listen = /run/php/php7.2-fpm.sock pm = dynamic pm.max_children = 150 pm.start_servers = 4 pm.min_spare_servers = 1 pm.max_spare_servers = 8 pm.max_requests = 250 /etc/nginx/nginx.conf:
user www-data; worker_processes auto; pid /run/nginx.pid; include /etc/nginx/modules-enabled/*.conf; events { worker_connections 2048; multi_accept off; } http { ## # Basic Settings ## sendfile on; tcp_nopush on; tcp_nodelay on; types_hash_max_size 2048; # server_tokens off; client_body_buffer_size 10K; client_header_buffer_size 1k; client_max_body_size 100m; large_client_header_buffers 4 8k; fastcgi_buffers 16 16k; fastcgi_buffer_size 32k; client_body_timeout 12; client_header_timeout 12; keepalive_timeout 15; send_timeout 10; # 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; # add_header Strict-Transport-Security "max-age=15768000; includeSubDomains" always; ## # Logging Settings ## access_log /var/log/nginx/access.log; error_log /var/log/nginx/error.log; ## # Gzip Settings ## gzip on; gzip_comp_level 2; gzip_min_length 1000; gzip_proxied expired no-cache no-store private auth; gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript; # 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/*; } /etc/nginx/sites-available/[SITENAME]:
server { listen 443 ssl http2; # managed by Certbot ssl_certificate /etc/letsencrypt/live/[SITENAME]/fullchain.pem; # managed by Certbot ssl_certificate_key /etc/letsencrypt/live/[SITENAME]/privkey.pem; # managed by Certbot #include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot ssl_ciphers EECDH+CHACHA20:EECDH+AES128:RSA+AES128:EECDH+AES256:RSA+AES256:EECDH+3DES:RSA+3DES:!MD5; ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot server_name [SITENAME]; root /home/[SITENAME]/domains/[SITENAME]/public_html/web; index index.php index.html index.htm index.nginx-debian.html; location / { #try_files $uri $uri/ =404; try_files $uri $uri/ /index.php?$query_string; } location ~ \.php$ { include snippets/fastcgi-php.conf; fastcgi_pass unix:/var/run/php/php7.2-fpm.sock; } } server { listen 443 ssl; # managed by Certbot server_name [SITENAME]; return 301 https://[SITENAME]$request_uri; ssl_certificate /etc/letsencrypt/live/[SITENAME]/fullchain.pem; # managed by Certbot ssl_certificate_key /etc/letsencrypt/live/[SITENAME]/privkey.pem; # managed by Certbot } server { if ($host = [SITENAME]) { return 301 https://$host$request_uri; } # managed by Certbot listen 80; server_name [SITENAME]; return 404; # managed by Certbot } server { listen 80; if ($host = [SITENAME]) { return 301 https://$host$request_uri; } # managed by Certbot server_name [SITENAME]; return 404; # managed by Certbot } 