Quoting Henrik Nordstrom <[EMAIL PROTECTED]>:

> tor 2006-03-16 klockan 15:14 +0200 skrev [EMAIL PROTECTED]:
> 
> > Do you mean no_cache in the request/reply http headers?
> 
> No, in squid.conf...

mmm... I worked with squid almost a year & didn't see this option ([EMAIL 
PROTECTED]) I will
check how everything works when it's disabled.
I hope this is the solution I was looking for.

> 
> > "last modified" and sometimes "expire" also in cache_control I set new
> type
> > "Dynamic" that I got squid to recognize (as CC_DYNAMIC) & treat as
> cachable
> 
> Why adding a new CC flag? Can't you use the max-age or s-max-age already
> defined for this purpose? Or perhaps public?
> 
> From the protocol point of view, just adding a Expires or CC
> max-age/s-max-age is sufficient to indicate the object may be cached.
> The only thing special about query URLS in the standard is that they
> SHOULD NOT be cached unless there is explicit freshness information
> available.
> 
> RFC 2616 13.9 Side Effects of GET and HEAD
> 
>    Unless the origin server explicitly prohibits the caching of their
>    responses, the application of GET and HEAD methods to any resources
>    SHOULD NOT have side effects that would lead to erroneous behavior if
>    these responses are taken from a cache. They MAY still have side
>    effects, but a cache is not required to consider such side effects in
>    its caching decisions. Caches are always expected to observe an
>    origin server's explicit restrictions on caching.
> 
>    We note one exception to this rule: since some applications have
>    traditionally used GETs and HEADs with query URLs (those containing a
>    "?" in the rel_path part) to perform operations with significant side
>    effects, caches MUST NOT treat responses to such URIs as fresh unless
>    the server provides an explicit expiration time. This specifically
>    means that responses from HTTP/1.0 servers for such URIs SHOULD NOT
>    be taken from a cache. See section 9.1.1 for related information.
> 
> 
> This (the last paragraph) is the reason why the no_cache lines exists in
> the recommended configuration by default as we do not have anything in
> the code implementing this exception, but in reality the lines is not
> needed to comply with the standard as long as min age is kept at 0 in
> refresh_pattern.
> 
> What this means is that if you remove the no_cache rules from your
> squid.conf then Squid will not have any exceptions for query URLs than
> they will be processed just like any other URL, just looking at the
> headers returned.

I used this header type in order to track it in squid & use a statistical cost
function only for dynamic type (no need to change the way regular files are
being cached).

> 
> Regards
> Henrik
> 


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