On 03/11/2014 08:05 AM, Omid Kosari wrote: > Is it possible for Squid to automatically find every similar object based on > something like md5 of objects and serve them to clients without need custom > DB ? No, because clients do not tell Squid what checksum they are looking for. They only give Squid a URL of the object (essentially). Thus, to satisfy request for URL A with an already cached response to request B, Squid needs to map URL A to URL B, and that is what Store ID does. Response B checksum is irrelevant until you do the URL mapping. > I know it is complicated task but i think the Utopia of a cache should be > that we just have one instance of an object in all Squid Farm > (automatically) and serve it as different URLs. It is possible to avoid caching duplicate content, but that allows you to handle cache hits more efficiently. It does not help with cache misses (when the URL requested by the client has not been seen before). If content publishers start publishing content checksums and browsers automatically add those checksums to requests, then you would have the Utopia you dream about :-). This will not happen while content publishers benefit from getting client requests more than they suffer from serving those requests. Cheers, Alex.