The invention discloses a method for reducing the overall overhead of
cloud storage in the presence of a
data dependence relationship. The method comprises two parts including a data storage
decision model and a data storage strategy decision
algorithm. In the data storage
decision model, a decision variable of the model is a data storage strategy, and comprises non-storage, multi-replica storage and
erasure code storage; a constraint condition of the model is that
data availability requirements satisfy a given availability index; an optimization target of the model is that the overall overhead of the
system is minimized, wherein the data overall overhead can simultaneously comprise storage overhead and calculation overhead; in the calculation overhead, the data
generation time is a random variable; an expected calculation method is given in the invention; in the data storage strategy decision
algorithm, when new data is generated, the data storage strategy is directly decided; and, when each decision period is ended, the data storage strategy in a communication
branch is updated by respectively using a
genetic algorithm or a traversal
pruning algorithm in manners of taking the communication
branch in a dependence relationship graph as a unit and judging whether the node number of the communication
branch is greater than a threshold value or not. Compared with the prior art, the method provided by the invention has the
advantage that: on the premise that the
data availability is ensured, the overall overhead of the
system is reduced.