[squid-users] refresh_stale_hit, collapsed_forwarding and Cache-Control: no-cache request headers

When:
   *refresh_stale_hit and collapsed_forwarding are both active, and
   * the request contains a Cache-Control: no-cache directive, and
   * multiple requests arrive within the refresh_stale_hit window

the first request will go forward as expected, but subsequent
requests get collapsed and effectively block, instead of being served
from cache.

In other words, requests with CC: no-cache (or Pragma: nc, I'm
guessing) effectively make *all* requests for the URI have a no-cache
directive for the span of the refresh_stale_hit window, if
collapsed_forwarding is on.

This isn't desirable, but it's not a huge deal; just thought I should
mention it in case somebody got near this code again.

Cheers,

--
Mark Nottingham
mnot@yahoo-inc.com