I believe it is something like a hash table, yes. I made some changes to our local squid source, and remember seeing something like this. Check out src\store_key_md5.cc (storeKeyPublic, etc). Hopefully that's a good starting point. -----Original Message----- From: Henry Yuan [mailto:forwardmy@xxxxxxxxx] Sent: Friday, April 22, 2011 4:59 PM To: squid-users@xxxxxxxxxxxxxxx Subject: What data structure does Squid use to store the cached content? So let's say it's looking for a http://website/webpage, then a lookup need to be done on "(http://)website/webpage". What data structure does Squid use to store these addresses? Is it something like a hash table? I tried to find it out myself from the source code, but Squid is a fairly not small code base. Would some one point me where in the source file I should look at? Thanks, Henry