Re: Cache-DIGEST false hits

---------- Forwarded message ----------
To: rousskov@nlanr.net (Alex Rousskov)
Subject: Re: Cache-DIGEST false hits
Newsgroups: infonet.lists.squid-users
X-Newsreader: TIN [UNIX 1.3 950824BETA PL0]

In article <Pine.SGI.3.96.980821084327.1869A-100000@Meta-Bug> you wrote:
> On Fri, 21 Aug 1998, Serge Krashakov wrote:
>
> > I have studied log files since today midnight and found that all false
> > CACHE_DIGEST_HITs resulst from URLs containing cgi-bin, .cgi, ? , and
> > from some hosts like ad.doubleclick.net, counter.rambler.ru,
> > www.asiannet.com and www.mirabilis.com.
> >
> > Both servers have the same refresh rules.
>
> A's refresh rules are probably irrelevant in this case. Note that proxy A has
> nothing but a URL when it forwards the request to B. Thus, refresh rules
> cannot be used on A's side. What we should investigate is how to prevent the
> object from being included into the B's digest. There is some logic in Squid
> that prevents some objects from getting into the digest. However, there are
> probably conditions that we could miss (e.g. uncachable objects like
> 'cgi-bin' or '?' should not go into the digest). The analysis of the refresh
> rules being fired on B's side will help.

cache_stoplist cgi ? & ; = .asp
hierarchy_stoplist same.

# Skip caching urls with strings between two / that are too long to be serious
cache_stoplist_pattern [^/]{40,}
# Skip caching URLs that are simply much too long
cache_stoplist_pattern ://[.]{250,}

 This is what I'm running. Stops altavista, and many other dynamic
 urls from being cached and queried.

 I'd suggest to put these (at least cache_stoplist) into default config.

 PS. if reply then to andre@online.ee
Received on Wed Sep 16 1998 - 10:44:30 MDT