Understand "hit for pass" cache objects

[Rob S]

Justin Pasher wrote:
> Hello,
>
> Herein lies my dilemma. A request for the same URL 
> (http://www.example.com/) is sometimes cacheable and sometimes not 
> cacheable (it usually depends on whether it's the first time a user 
> visits the site and the Set-Cookie header has to be sent). What this 
> means is if I have a very heavy hit URL as a landing page from Google, 
> most of the time there will be a "hit for pass" cache object in Varnish, 
> since most people going to that page will have a Set-Cookie header.

Justin,

Rather than answer your question (which other people are answering), I'd 
suggest you reconsider using sessions and selectively caching full 
pages.  There are several other solutions that might work for you - for 
example, including personalised content via ESI, or overlaying it 
client-side with javascript.  We're using a combination of these to 
great effect - and ensure that any page containing a session cookie is 
never cached.

Obviously the based answer would depend on the nature of your apps, but 
it might be worth looking at in the longer term.  There's more than one 
way to crack an egg.



Rob