[Zope] Re: Accelerating images without proxy

Marc Burgauer marc@sharedbase.com
Tue, 22 Apr 2003 23:43:43 +0100


> Images delivered by zope are quite extensively cached on the browser
> side per default, even without configuring something in zope.
> I.e. zope sends appropriate "not modified" headers if it gets the right
> request from the browser (which nearly all browsers do). You can see
> this when grepping the logs for "304", or using a log analyzer. I just
> checked on two sites of us, and on one, which has many different images,
> I get 10% of all responses to be "304", while on the other, whose images
> consist mainly of navigation buttons, I get 50% of all images cached.
> This was btw. a big problem for us using localizer, because when
> switching languages because the images wouldn't change.
> 
> Since sending the 304 shouldn't be expensive, I doubt it will help much
> for the speed of the site, but esp. not if it is network I/O bound.
> 
> One thing which is important is to link the navigation images with their
> absolute url, not using acquisition, so that the browser will be able to
> see that the images are identical.

I checked the logs and then some HTML. We did tell the web designers
(customer's choice of design agency) to reference all images with absolute
url (well, always start with the slash, e.g "/images/navigation/home.gif",
but they didn't (so they are: "images/navigation/home.gif"). And there are
hardly any 304 codes in the log.

Would in this case an  Accelerated HTTP Cache Manager help?

I am afraid I would need to skim through about 100 files and change the HTML
otherwise. 

Cheers

Marc