fastcgi_param QUERY_STRING "map=/srv/imagery/mapserver/layer-<%= @layer %>.map&mode=tile&layers=<%= @layer %>&tilemode=gmap&tile=$2+$3+$1";
fastcgi_pass "<%= @site %>_fastcgi";
fastcgi_buffers 8 64k;
+ fastcgi_busy_buffers_size 64k;
include fastcgi_params;
fastcgi_param REQUEST_METHOD "GET";
fastcgi_param HTTP_PROXY "";
# Free connection to socket for other requests
fastcgi_keep_conn off;
- fastcgi_cache_lock on;
- fastcgi_cache_lock_timeout 30s;
fastcgi_cache_valid 200 21d;
+
+ # Serve stale cache on errors or if updating
fastcgi_cache_use_stale error timeout updating http_500 http_503;
+ # If in cache as stale, serve stale and update in background
+ fastcgi_cache_background_update on;
+ # Enable revalidation using If-Modified-Since and If-None-Match for stale items
+ fastcgi_cache_revalidate on;
+
+ keepalive_requests 0;
- # Leaflet aborts connection still in flight to free up resources
- fastcgi_ignore_client_abort off;
+ # Ignore client abort as it causes issues with the pipeline
+ fastcgi_ignore_client_abort on;
fastcgi_catch_stderr "Image handling error";
fastcgi_next_upstream error timeout invalid_header http_500 http_503;
- fastcgi_next_upstream_tries 3;
+ fastcgi_next_upstream_tries 8;
# Do not GZIP tiles
gzip off;
# Add HTTP Cache-Control + Expires Headers
expires 7d;
+ add_header Cache-Control "stale-while-revalidate=604800, stale-if-error=604800";
+ add_header x-cache-status $upstream_cache_status;
# Allow CORS requests
add_header 'Access-Control-Allow-Origin' '*';