Distributed storage system and distributed storage method

A distributed storage system, comprising:

• a plurality of data storage nodes that store a plurality of object data items in a distributed manner, wherein
• each of the plurality of object data items is characterized by a data coordinate defined in a space and uniquely identified by a data identifier,
• each of the plurality of data storage nodes is assigned a node coordinate defined in the space,
• the distributed storage system is configured to select, for one of the plurality object data items, a plurality of data storage nodes as first data storage nodes from among the plurality of data storage nodes, distances between the node coordinates assigned to the plurality of first data storage nodes and the data coordinate characterizing the one object data item being shorter than distances between the node coordinates assigned to other storage nodes and the data coordinate characterizing the one object data item, and
• the distributed storage system is further configured to:
• assign a plurality of pseudo random numbers, generated using a data identifier of the one object data item as a seed, respectively, to the plurality of first data storage nodes;
• extract, from among the plurality of first data storage nodes, a data storage node, for which a value obtained by multiplying an assigned pseudo random number with a weight calculated according to a distance between a data coordinate of the one object data item and a node coordinate assigned to the data storage node is maximum among the plurality of first data storage nodes;
• and
• determine the extracted data storage node as a data storage node to store the one object data item.