Hello! On Thu, Jan 28, 2016 at 07:13:11PM -0500, jeeeff wrote:
> My understanding of proxy_cache_lock is that only one request should be > passed to the proxied server for a given uri, even if many requests from the > same uri/key are hitting nginx while it is being refreshed. > > When the cache folder specified in the proxy_cache_path is empty, it works > well and behave like I described above. > However, if the element in the cache already exists, but is expired > (according to proxy_cache_valid configuration), all concurrent requests will > hit the proxied server and the resource will be downloaded multiple times. That's expected, see http://nginx.org/r/proxy_cache_lock: : When enabled, only one request at a time will be allowed to : populate a new cache element identified according to the : proxy_cache_key directive by passing a request to a proxied : server. Note "a new cache element". It does not work while updating cache elements, this is not implemented. [...] > Using "proxy_cache_use_stale updating" is also not an option since I want > all requests that are coming simultaneously to wait and use the new resource > when there is a new one returned from the proxied server. > > Is there something I am doing wrong, or is this the expected behavior? Is > there a way to do what I am trying to do with nginx? See above, this is expected behaviour - as of now proxy_cache_lock does nothing while updating cache elements. Using "proxy_cache_use_stale updating" is recommended if you need to reduce concurrency while updating cache elements. If "proxy_cache_use_stale updating" doesn't work for you, you may try extending "proxy_cache_lock" to also cover updating. Current implementation doesn't try to do this to reduce complexity. -- Maxim Dounin http://nginx.org/ _______________________________________________ nginx mailing list nginx@nginx.org http://mailman.nginx.org/mailman/listinfo/nginx
