Re: [squid-users] My cache is far away from full. But lots of thingsget released. Why?

Everything is possible with some coding, but doing this is a very gross
HTTP violation. Thre requirement that content marked with Cache-Control:
no-cache isn't cached by proxies is a very strong one for perfectly
valid reasons.

It is vastly better to make content providers understand the value of
caching and make their content cache friendly. Sure, it requires more
work to track these down, but the end result is far better with no risk
of unintentional caching of private information.

Completely ignoring no-cache is not an option

Sending IMS queries won't help as

a) 99.99% of all content marked with no-cache can't be validated with
IMS queries

b) The 0.01% which can is likely to get it wrong as it is not expected
by the origin servers, or only implemented for "Cache-Control: private"
and based on each users private copy, not a shared copy (as there can't
be one).

Regards
Henrik Nordström
Squid Hacker

Joao Pedro Clemente wrote:

> Have squid ( optionnally defined in the config file , and for some object
> tipes only defined by some
> rule like *.gif, *.jpg or whatever )
> that if these objects come with NO_CACHe directive from the web server ,
> then cache them and do one of these things in a later acess:
>
> a) Send an IMS to the server before returning the cached object
> b) Completely ignore the directive for xxxx seconds (defined in the
> config file where we asked this feature) since it was cached,
> and only then think of it as STALE (worst in my opinion, but would
> increase performance greatly if the objects rarely change)
>
> I had a proxy server in a win machine that had an option to disregard
> server control directives and... uau, "that was fast".
> However, that brought consistency problems , but as long as we do some ims
> query i dont see why not..
>
> Let me ask this in some other way :
> Why should I feel bad in caching some kind of objects (like jpg and gifs)
> when I look to squid reports to see that I have lot of uncached acesses
> to some website I know most of things rarely change?
> And if I use an IMS or semthing to confirm my tought about the objects,
> then why not to cache it , disregarding the site sayings?
Received on Mon Oct 08 2001 - 18:23:19 MDT