I think this solves the issue: http://hg.nginx.org/nginx/rev/9552758a786e
Thanks, JP On Wed, Mar 15, 2017 at 11:05 AM, Jean-Paul Hemelaar <[email protected]> wrote: > Hi, > > I noticed a delay of approx. 200ms when the proxy_cache_background_update > is used and Nginx sends stale content to the client. > > Current setup: > - Apache webserver as backend sending a slow response delay.php that > simply waits for 1 second: <?php usleep(1000000); ?> > - Nginx in front to cache the response, and send stale content it the > cache needs to be refreshed. > - wget sending a request from another machine > > Nginx config-block: > location /delay.php { > proxy_pass http://backend; > proxy_next_upstream error timeout invalid_header; > proxy_redirect http://$host:8000/ http://$host/; > proxy_buffering on; > proxy_connect_timeout 1; > proxy_read_timeout 30; > proxy_cache_background_update on; > > proxy_http_version 1.1; > proxy_set_header Connection ""; > > proxy_cache STATIC; > proxy_cache_key "$scheme$host$request_uri"; > proxy_cache_use_stale error timeout invalid_header updating http_500 > http_502 http_503 http_504; > proxy_set_header Host $host; > proxy_set_header X-Real-IP $remote_addr; > proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; > proxy_set_header Accept-Encoding ""; > > # Just to test if this caused the issue, but it doesn't change > tcp_nodelay on; > } > > Wget request: time wget --server-response --output-document=/dev/null " > http://www.example.com/delay.php?teststales=true"; > Snippet of wget output: X-Cached: STALE > Output of time command: real 0m0.253s > > Wget request: time wget --server-response --output-document=/dev/null " > http://www.example.com/delay.php?teststales=true"; > Snippet of wget output: X-Cached: UPDATING > Output of time command: real 0m0.022s > > So a cache HIT (not shown) or an UPDATING are fast, sending a STALE > response takes some time. > Tcpdump showed that all HTML content and headers are send immediately > after the request has been received, but the last package will be delayed; > that's why I tested the tcp_nodelay option in the config. > > I'm running version 1.11-10 with the patch provided by Maxim: > http://hg.nginx.org/nginx/rev/8b7fd958c59f > > Any idea's on this? > > Thanks, > > Jean-Paul >
_______________________________________________ nginx mailing list [email protected] http://mailman.nginx.org/mailman/listinfo/nginx
