[Zope-dev] [Caching] Inefficient HTML cache?

Dominic Hiles Dominic.Hiles at bristol.ac.uk
Tue Nov 23 07:55:38 EST 2004

Dear Dieter,

--On 20 November 2004 10:08 +0100 Dieter Maurer <dieter at handshake.de> wrote:

> We use Apache for caching and observe the following behaviour:
>   Apache requests the object from Zope and caches it until
>   the expiration date is reached. From then on, Apache
>   forwards "If-Modified-Since" requests to Zope, Zope
>   responds with an "304" response but without a new
>   expiration date! As Apache does not get new expiration info,
>   it continues to forward "If-Modified-Since" requests for
>   the object. This significantly reduces cache efficiency.
> In my view, Zope should include new expiration info in its
> "304" responses.
> The CachingManager API may need to be extended, to allow
> the HTTP CacheManager to add information to "304" responses.

We've noticed the same behaviour and, for that reason, have avoided using 
the HTTP CacheManager in Zope.  Instead, we handle headers (and 304 
responses) for "standard" pages in the main_template and the rest of the 
caching on Apache (using mod_expires for outbound responses).

+1 for fixing this behaviour.


More information about the Zope-Dev mailing list