Re: possible squid bugs [was: cacheability engine]

Duane Wessels wrote:

> And if the admin changes the refresh settings, the 'fresh-until' is
> wrong for some cached objects?

So? It is reevaluated on a cache hit.

> By my reading of RFC2616, Age must be based on Date: (unless the
> response already has an Age value). last-validated alone is not enough
> to calculate Age.

Well, the cache is allowed to update headers from a validations (HEAD or
304 replies). Date is not excluded from this as far as I can tell.

> stale date headers? How can a date header be stale? Caches aren't supposed
> to update the date header.

Actually a cache must update the Date header after cache revalidation
for hierarchical caching to work properly, or else content is "always"
stale at the second level caches (including browser caches). This is
because the Age calculation is a max of the Age header and Now-Date, so
the only way for a cache to propagate the validated status downwards to
the next cache is by updating the Date header with the new validated
timestamp.

/Henrik
Received on Thu Mar 30 2000 - 14:37:41 MST