Automated tiering system and automated tiering method

An automated tiering method, adapted for a storage system having a plurality of storage apparatuses layered into at least two tiers and a controller, the method comprising:

• choosing one of a plurality of system configurations applied for a data relocation function by the controller;
• executing an algorithm analyzer corresponding to the chosen system configuration, analyzing a plurality of data blocks in each of the storage apparatuses to determine a target block of each of the data blocks after relocation, and generating an estimated data allocation map based on the determined target blocks by the controller;
• executing a simulation engine by the controller to classify the target blocks in the data allocation map based on usage frequency, so as to generate an exploitation map;
• repeating the steps by the controller to generate the data allocation map and the exploitation map corresponding to each of the system configurations;
• evaluating the exploitation maps by the controller to find out the system configuration raising the most performance as a best configuration;
• and
• executing a data migrator by the controller to migrate the data blocks in the storage apparatuses based on the best configuration.