2 Replies Latest reply: Mar 7, 2011 10:06 PM by Solaria RSS

    WebCache not caching files

      Hi all,

      i have application server 10g (9.0.4) with serveral applications deployed in multiple OC4J instances.

      There is a rule that instruct webcache to cache all image files (gif,jpg,png,etc) this rule is working good except for one application.

      In webcache admin -> popular requests (not cached) i can see the reason these files are not cached.

      Webcache matches the rule for caching images but , it "chooses" not to cache with the following reason: BY_SURROGATE_CONTROL_HEADER

      Reading from the webcache admin manual i get litte info:

      Cache Reason: The reason that the object is cached or not cached. Possible values are:

      o BY_SURROGATE_CONTROL_HEADER: Cached or not cached because of information in the Surrogate-Control response header.

      I just don't understand these Surrogate-Control response header.

      I have reported this issue to application developer that claim they have no code enabling/disabling the caching of pages.

      Can you give me some clarification in this issue ? what is surrogate-control header ? if this surrogate control is generated by application , how can i detect it ? how can i handle it ?

      My Environment

      Oracle application server 10g (9.0.4) on windows 2003 server
      Application built with BC4J framework

      Best Regards

      Rui Madaleno
        • 1. Re: WebCache not caching files
          Found the problem !

          The application deployed is protected with SSO, and SSO ads a control header to the pages that is protecting so it don't get cached.

          the "workaround" is modify the mod_osso.conf file, edit the <location> tag to include the
          OssoSendCacheHeaders directive.


          <LocationMatch "/wfat/img">
          OssoSendCacheHeaders off

          Best Regards

          Rui Madaleno
          • 2. Re: WebCache not caching files
            Our remote users have complained for months about slow application response. By making this one, simple change to mod_osso.conf, the application performance has increased dramatically...

            Good Job!

            So... what other unfortunate defaults are there that I don't know about? (already found out that leaving "shared_servers" at "1" is a really bad idea.)