title: Nginx automatically deletes cache which is set to be valid longer?
body: <p>I set up a Nginx reverse proxy server serving mp4 files hosted on another server. Everything is working fine now except the cache. Although I have <code>proxy_cache_valid</code> set to 1 day (<code>proxy_cache_valid  any 1d</code>), the cache will be automatically deleted after a short amount of time (5-10 mins I think). My file sizes range from 200 - 1500MB (700MB in average).</p>
  
  <p>I couldn't figure out what's wrong with the configurations. Anything might help.</p>
  
  <p>Here are the configurations</p>
  
  <pre><code>worker_processes  auto;
  
  worker_rlimit_nofile 100000;
  
  events {
      worker_connections  5000;
      multi_accept on;
      use epoll;
  }
  
  
  http {
      include       mime.types;
      default_type  application/octet-stream;
  
      sendfile        on;
      tcp_nopush     on;
      tcp_nodelay on;
  
      keepalive_timeout  10;
      keepalive_requests 1024;
      client_body_timeout 12;
      client_header_timeout 12;
      send_timeout 10;
  
      proxy_cache_path /tmp/mycache keys_zone=mycache:10m use_temp_path=off;
      limit_conn_zone $binary_remote_addr zone=addr:10m;
      server {
          listen       80;
          server_name  localhost;
  
      access_log off;
  
          error_page   500 502 503 504  /50x.html;
          location = /50x.html {
              root   html;
          }
  
      open_file_cache max=10000 inactive=30s;
      open_file_cache_valid    60s;
      open_file_cache_min_uses 5;
      open_file_cache_errors   on;
  
      client_body_buffer_size 16K;
      client_header_buffer_size 1k;
      client_max_body_size 8m;
      large_client_header_buffers 2 1k;
  
          location / {
          proxy_cache mycache;
          proxy_max_temp_file_size 1924m;
          slice              100m;
          proxy_cache_key    $host$uri$slice_range;
          proxy_set_header   Range $slice_range;
          proxy_http_version 1.1;
          proxy_ignore_headers X-Accel-Expires Expires Cache-Control Set-Cookie; 
          proxy_cache_valid  any 1d;
          limit_conn addr 5;
          proxy_pass   http://domain2.com/;
          secure_link $arg_md5,$arg_expires;
          secure_link_md5 "secret$secure_link_expires$uri";
  
          if ($secure_link = "") { return 403; }
                  if ($secure_link = "0") { return 410; }
          }
  
      }
  
  }
  </code></pre>