[development] cache flexibility improvement

[Moshe Weitzman]

Well, most of those variables will never matter to an anon user and
those are the only ones eligible for page cache. But still, you have a
point. We discuss this at length at http://drupal.org/node/590614. I
even argued same as you. Please discuss there.

On Tue, Jan 12, 2010 at 10:09 AM, Ivan Sergio Borgonovo
<mail at webthatworks.it> wrote:
> Hi,
>
> I saw a chance to improve the flexibility of D7 cache, with
> something that looks as a very small change.
>
> I'm sorry if I'm missing something, but I'd really appreciate if
> someone will point out what's wrong with my proposal.
>
> Substantially D7 doesn't serve cached pages if $_SESSION isn't empty
> as stated in drupal_page_get_cache docs (I couldn't find anymore
> where $_SESSION is tested...).
>
> This limit the use of cache substantially.
> Nearly all users will have a not empty $_SESSION that will force
> regeneration of ALL the pages.
>
> Currently core put in SESSION:
> 1) openid
> 2) user_overview_filter
> 3) dblog_overview_filter
> 4) node_overview_filter
> 5) clean_url
> 6) authorize_filetransfer_backends
> 7) authorize_operation
> 8) ignore_slave_server
> 9) update_manager_update_projects
> 10) authorize_results
> 11) update_results
> 12) messages
> 13) locale_translation_filter
> 14) maintenance_mode
> 15) update_success
> 16) updates_remaining
> 17) maintenance_mode
> 18) batch_form_state
> 19) my_batch_results
> 20) batches
>
> Most of them shouldn't actually forbid the use of ALL cached pages.
> One way to retro-fit a more fine grained control over cache would be
> to add a field to all the SESSION items in the array
>
> eg.
> $_SESSION['session_var'] = $stuff;
> $_SESSION['session_var']['cacheable'] = true;
>
> And in spite of invalidating all cached pages we could check if
> there is any ['cacheable'] that is null/unset preserving current
> behaviour and giving a chance to exploit more the cache.
>
> Then we could add the ['cacheable'] flag where it is safe a bit at a
> time.
>
> If
> bootstrap_invoke_all('boot')
> in function _drupal_bootstrap_page_cache()
> could be anticipated we could even give a chance to modules that
> would like to control if the cache has to be used to fire.
> eg. don't serve cached pages for user coming from this IP, don't
> serve cached pages during these hours, always serve cached pages to
> these IP etc...
>
> --
> Ivan Sergio Borgonovo
> http://www.webthatworks.it
>
>