Re: miss_access and being nice.

Hi Buce.

Yes, you're making sense - I actually wrote to the list about this very
things a few weeks back. The answer at the moment is to allow the
cache-digest sibling to have miss_access on your server. When
experimenting with that with a sibling cache of ours we could between a 20
and 40% miss rate hence they were using us for transit.

Naturally we don't use cache-digests anymore. The idea is sound but you
must remember that it's still beta code and will be improved on in the
future to accomodate us all I'd say :-)

Regards

At 03:54 PM 4/11/98 +1000, Bruce Campbell wrote:
>Is it possible to be nice, and rather than returning an error page on a
>false cache hit, return the page?
>
>ie with;
>
>client -> Proxy A -(cache_digest_hit)-> Proxy B -> Internet
>
>a) Proxy B does not want to spend money, so has miss_access deny proxy A.
> Possible to have 'limited' miss_access? (ie, if its a miss *and* that
> url could have been in the last cache_digest, fetch the url?)
>
>*or*
>
>b) Proxy A notices that it got 403 returned *and* the last line of the
> returned page matched 'Generated.* by remote_proxy_name (Squid.*)', and
> tries to fetch the url again from another proxy or directly.
>
>Easily seen problems; With (a), ProxyA can cause a DoS on ProxyB since
>ProxyB must look up each url in the previous/current cache_digest under
>high load (cpu usage goes through the roof).
>
>With (b), error messages can be changed (though usually the above regex
>would work); ProxyA needs to keep track of which of its peers it
>has/hasn't tried for that url. Also proxyA needs to lower proxyB's
>priority slightly if repeated 403s are generated by proxyB.

--
This message is Copyright (C) 1998 by Karl Ferguson
Tower Networking Pty Ltd t/a STAR Online Services
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