Thanks, Maxim, for correcting my misunderstanding. With what frequency is the cache manger run?
Roger > On Apr 3, 2020, at 9:26 AM, Maxim Dounin <mdou...@mdounin.ru> wrote: > > Hello! > > On Fri, Apr 03, 2020 at 08:33:43AM -0700, Roger Fischer wrote: > >>> You can just set the inactive time longer than your possible maximum expire >>> time for the objects then the cache manager won't purge the cache files >>> even the object is still valid but not accessed. >> >> That may only have a small impact. >> >> As far as I understand: >> NGINX will remove an item only when the cache is full (ie. it needs space >> for a new item). >> Items are removed based on the least-recently used (LRU) queue. >> The least-recently-used (last) item in the LRU queue is unconditionally >> removed. >> The second and third last items are removed if they are past the invalid >> time. > > Your understanding is wrong. Cache manager always removes all > items which were not access for the "inactive=" period of time. > Quoting docs (http://nginx.org/r/proxy_cache_path): > > : Cached data that are not accessed during the time specified by the > : inactive parameter get removed from the cache regardless of their > : freshness. By default, inactive is set to 10 minutes. > > See ngx_http_file_cache_expire() function for details. > > Additionally, cache items can be removed based on the "max_size=" > parameter of the "proxy_cache_path" directive, or if there isn't > enough room in the "keys_zone=" shared memory zone. > >> The expiry of an item has no influence on the removal of items. >> It only affects if the item is delivered from the cache, or >> revalidated with an upstream request. > > That's correct, as long as "expire" is meant to be the time from the > Expires / X-Accel-Expires / Cache-Control / proxy_cache_valid. In > nginx documentation this is called "caching time". > > -- > Maxim Dounin > http://mdounin.ru/ > _______________________________________________ > nginx mailing list > nginx@nginx.org > http://mailman.nginx.org/mailman/listinfo/nginx _______________________________________________ nginx mailing list nginx@nginx.org http://mailman.nginx.org/mailman/listinfo/nginx
