More IMS

When an object in Squid's cache expires, it emits an IMS request to the
server for this object. However, it seems to me that the cached object is
not updated with the new cacheability information (at least assuming the
304 response has no Last-Modified header to compare with the old in
httpReplyValidatorsMatch). This means that, once an object expires in
cache, the cache will continue issuing IMS requests to the origin server
on every request to this object, at least until the object changes on the
server and a new 200 response comes back.

Am I understanding this correctly? It seems the max age in the refresh
value is having no effect on this.

Also, in response to the last IMS question, it looks like I'm seeing two
requests (in Ethereal and in the squid logs) when a Squid originated IMS
request to the server comes back as having changed (200). They are both
IMS requests. I'm not sure what logic is creating this, but it could be
the test mentioned in the previous email. I can send these logs if people
are interested.

Leeann
Received on Tue Apr 20 2004 - 15:34:32 MDT