Mike Leong wrote:
Hi,
I'm currently using squid to reverse proxy cgi requests to our
backend. I'm currently using some really aggressive refresh_pattern
rules to make sure cache objects never get automatically purged. If
something got changed in our backend servers, I manually purge the
affected objects.
As the number of objects being cached increase, it's getting more
difficult to purge stuff. We're prepare to fix our backend webservers
to do whatever it takes to make it such that squid can fetch new fresh
objects, should anything in the backend get updated.
My question is, what can we do to our backend to accomplish this.
Currently, here's a sample header, dumped from a cache object:
HTTP/1.1 200 OK
Set-Cookie: blabla Expires=Sun, 08-Jul-2007 08:53:52 GMT #1 year from
request
TokenId: token-5102989651042811735-115234883242417937
Content-Type: image/jpeg
Content-Length: 18765
Date: Sat, 08 Jul 2006 08:53:52 GMT
Server: Apache-Coyote/1.1
Connection: Keep-Alive
We can probably add any other http header related to cache control, w/
the exception of expiration date, since we have no idea when new data
will be modified in the backend.
thx
mike
http://www.web-caching.com/mnot_tutorial/tips.html#SCRIPT
The whole tutorial is a good read, but this section deals specifically
with writing cacheable scripts.
Chris
