In nginx I am using the
directive (http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_cache_use_stale) so that concurrent request to an invalidated cached content only send 1 request to the upstream (the non-first request respond with stale content while the first request is updating the content).
this works well.
Now is there a way to also have the first request respond immediately with stale content, while at the same time triggering the update ?
right now, the response time is very good for non-first invalidating request, but the first one needs to wait until the backend responds. I would prefer serving stale content until the cache is updated.