An appliance o for evicting data based on traffic priority of data is described. The appliance has one or more processors and includes a compression history manager configured to acquire traffic priority information of data, the data being conveyed over a connection and to assign a compression history set based on the traffic priority information of the data. The compression history manager is also configured to, if cache space does not exist to store the data and another compression history set corresponds to lower traffic priority in a cache queue, evict data from the other compression history set corresponding to lower traffic priority.