Fortifying Craft for High Traffic https://speakerdeck.com/rungta/fortifying-craft-for-high-traffic

_init.twig

{# _init.twig #}
{#
  Usage
  
  extend `_init`
  set `doNotCache` to true to exclude a page
  set `cacheKey` to a string to cache a template globally
    (as opposed to by URL). eg: 404 template
  modify `cacheKeyPrefix` to include variation params, if any
#}

{# Cache Config #}
{% set cacheflags = cacheflags ?? 'entries|assets|globals|categories|users' %}
{% set cacheKeyPrefix = {
  device: craft.app.request.isMobileBrowser ? 'mobile' : 'nonmobile',
  user: currentUser ? 'user' : 'guest',
}|join(',') %}
{% set cacheableEnv = craft.app.request.isPost
  and not (doNotCache ?? false)
  and not craft.app.session.hasFlash('error')
  and not craft.app.session.hasFlash('notice')
%}


{# Figure out if page should be cached #}
{%- if cacheableEnv %}
  
  {# If a cacheKey is set, use that to globally cache the rendered page #}
  {% if cacheKey ?? false %}
    {% cacheflag flagged cacheflags globally using key (cacheKeyPrefix ~ ':' ~ cacheKey) for 1 month %}
      {%- minify html %}
        {{ block('html') }}
      {% endminify -%}
    {% endcacheflag %}
    
  {% else %}
    
    {# No cacheKey set, cache the rendered page by url (not globally) #}
    {% cacheflag flagged cacheflags using key cacheKeyPrefix for 1 month %}
      {%- minify html %}
        {{ block('html') }}
      {% endminify -%}
    {% endcacheflag %}
  {% endif %}
  
{% else %}
  {% block html %}{% endblock %}
{% endif %}

nginx.conf

#
# WARNING: This is not a complete NGINX configuration file
# It tries to highlight just the directives used to enable FastCGI microcaching
# as explained in https://speakerdeck.com/rungta/fortifying-craft-for-high-traffic
#

http {
    #...
    
    # Init cache
    fastcgi_cache_path /var/run/fastcgicache levels=1:2 keys_zone=fastcgicache:100m inactive=1d;
    
    # Configure
    fastcgi_cache_lock on;
    fastcgi_cache_use_stale updating error timeout invalid_header http_500;
    fastcgi_cache_background_update on;
    fastcgi_cache_methods GET HEAD;
    fastcgi_cache_key "$scheme$request_method$host$request_uri";
    
    # Detect mobile browsers
    # from https://gist.github.com/dangayle/2919206 
    # map $http_user_agent $is_mobile {
    #  default 0;
    #  "~*android.+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|symbian|treo|up\.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino" 1;
    #  "~*^(1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(di|rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-)" 1;
    # }
    # fastcgi_cache_key "$is_mobile$scheme$request_method$host$request_uri";
    
    # Cache status (debug)
    add_header X-Cache $upstream_cache_status;
    fastcgi_pass_header X-Accel-Expires;
    
    server {
        #...
        
        # Craft-specific location handlers to ensure AdminCP requests route through index.php
        # If you change your `cpTrigger`, change it here as well
        location ^~ /admin {
          try_files $uri $uri/ @phpfpm_nocache;
        }
        location ^~ /actions/ {
          try_files $uri $uri/ @phpfpm_nocache;
        }
        location ^~ /index.php/admin {
          try_files $uri $uri/ @phpfpm_nocache;
        }
        location ^~ /index.php/actions {
          try_files $uri $uri/ @phpfpm_nocache;
        }
        
        location ~ \.php$ {
            # Enable cache
            fastcgi_cache fastcgicache;
            fastcgi_ignore_headers Cache-Control Expires;
            fastcgi_cache_valid 200 301 302 404 1s;
            fastcgi_cache_bypass $arg_token $cookie_1031b8c41dfff97a311a7ac99863bdc5_identity;
            fastcgi_no_cache     $arg_token $cookie_1031b8c41dfff97a311a7ac99863bdc5_identity;
            
            # Regular PHP handling
            # ...
        }
        
        location @phpfpm_nocache {
            # No FastCGI Cache
            fastcgi_cache_bypass 1;
            fastcgi_no_cache 1;
          
            # Regular PHP handling
            # ...
        }
    }
}