Why Aerospike Use 5G virtual memory but Redis uses much less virtual memory


Our data set is not big,I would store data purely in 2GiB memory.If we are working on 2GiB memory limiation,Is it possible for us to use aerospike for my requirement? I saw ,for example,Redis which support smaller dataset,but only use 42M virtual memory.Why aerospike withholds so big virtual memory before using it?What is the difference between Community Version and Enterprise Version as to Memory allocation and configuration.