Posted by srjosh on October 6, 2010 at 8:31pm
pressflow and varnish work best together with external caching turned on, correct?
but External caching mode skips boot and exit hooks.
However, path_alias_cache uses hook_exit to set the paths into cache.
Are these two modes incompatible?
i.e. does varnish caching with external preclude path alias caching?
If not, any ideas what I'm missing? If so, anyone have a workaround?

Comments
My understanding is that if a
My understanding is that if a request misses the Varnish cache, then a complete bootstrap and page load is performed, which will populate the path alias cache.
--
Dave Hansen-Lange
Director of Technical Strategy, Advomatic.com
Pronouns: he/him/his
so do we enable
so do we enable path_alias_cache or disable external caching ? Im trying to set up pantheon right now..........
www.thecenterofthenet.com
http://cn.linkedin.com/in/roberpteatonjr
http://www.facebook.com/robertp.eaton
http://www.alamy.com/stock-photography/6A42F1A1-E40A-48FD-8C7F-FF258A401...
I agree with Dalin. Hook exit
I agree with Dalin. Hook exit is only skipped when a page is pulled out of either the aggressive cache, or the external cache. If a user is logged in, or if the page is not in cache, then exit is pulled and the path alias cache is used.
The warning you get for what modules are incompatible is not anything intelligent, it just does a check to see if they call hook_boot or hook_exit.
Definitely turn it on. You won't get huge use out of the cache, but it is preferable to not having it on at all.