Varnish and squid, *again*

Just listened to Artur railing against squid and preaching the virtues of varnish. He quoted what most people quoted, which is how varnish performs serving out of *memory*. It must be nice to have a working set that small. Until someone can show me numbers of disk-intensive (meaning, full caches, LRU eviction churning all the
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Squid patch for making “time” stats more meaningful.

Thanks to Mark, squid’s got a patch I’ve been wanting for a gazillion years: time-to-serve statistics that don’t include the client’s location Normally, squid’s kept statistics that included the “time” to serve an object, whether it be a HIT, MISS, NEAR HIT, etc. The clock starts for this time when the first headers are
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Caches and Eviction Policies

Caching systems are finite in size. So what happens when your cache is filled with objects ? No more objects ? Game over ? Hopefully, no. Most modern caches have some form of replacement or eviction policy. What means that based on some criteria, it’ll figure out what objects to throw out the window so
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Varnish and the state of web caching

So there’s lots of excitement around Varnish, which is a caching proxy that is built to be first and foremost a reverse-proxy, as opposed to squid, which does both forward and reverse. Acceleration (reverse-proxying) is obviously important to us at Flickr, as we use squid extensively.