Research on Improvement of Dynamic Load Balancing in MongoDB

As a representative of NO-SQL database, MongoDB is widely preferred for its automatic load-balancing to some extent, which including distributing read load to secondary node to reduce the load of primary one and auto-sharding to reduce the load onspecific node through automatically split data and migrate some ofthem to other nodes. However, on one hand, this process is storage-load -- Cbased, which can't meet the demand due to the facts that some particular data are accessed much more frequently than others and the 'heat' is not constant as time going on, thus the load on a node keeps changing even if with unchanged data. On the other hand, data migration will bring out too much cost to affect performance of system. In this paper, we will focus on the mechanism of automatic load balancing of MongoDB and proposean heat-based dynamic load balancing mechanism with much less cost.