Squid internal overview

Squid storage manager (ctd)
What is a memObject ?
Stores the state data for store clients and the store server
Keeps state for any memory pages associated with the StoreEntry
A single memObject ONLY references one StoreEntry, and vice versa

Memory use
Uses a stmem list, which is a single linked list of fixed page sizes
Memory at the beginning of the object which is not being used can be freed, allowing squid to handle very very large objects
Objects up to a given size (maxInMemObjectSize) are not freed aggressively like large objects, to increase the memory hit-rate
Memory is aggressively freed during storeAppend(), and smaller objects are also considered for removal to make way for the new data