A computer-implemented method, comprising: receiving a first key; determining a second hash map associated with the first key from among a plurality of hash maps, each of said plurality of hash maps being stored on one of a plurality of nodes (110, 112) of a distributed computing system, individual hash maps mapping a set of keys to particular index values, wherein the second hash map associated with the first key is configured to be loaded into on-board memory of an electronic device comprising one of said nodes, wherein determining the second hash map associated with the first key from among the plurality of hash maps comprises: hashing the first key to produce a hashed key; obtaining a first hash map that maps a set of hashed keys to the plurality of hash maps, the first hash map being configured to be loaded into on-board memory of one of said nodes; inputting the hashed key into the first hash map; and outputting an identifier of the second hash map corresponding to the hashed key; determining an index value associated with a second key using the determined second hash map, wherein utilizing the plurality of hash maps to determine the second hash map associated with the first key enables a lookup to be performed on said second hash map to determine the index value using the on-board memory of the electronic device; and determining transaction processing data associated with the first key using the determined index value, wherein determining transaction processing data associated with the first key using the determined index value comprises: obtaining an indexed list, the indexed list mapping a plurality of index values to a plurality of transaction processing data, the indexed list being stored in a centralized data store of the distributed computing system; inputting the index value into the indexed list; and outputting the transaction processing data corresponding to the index value; and providing the determined transaction processing data, wherein the first key and the second key are the same. receiving a first key; determining a second hash map associated with the first key from among a plurality of hash maps, each of said plurality of hash maps being stored on one of a plurality of nodes (110, 112) of a distributed computing system, individual hash maps mapping a set of keys to particular index values, wherein the second hash map associated with the first key is configured to be loaded into on-board memory of an electronic device comprising one of said nodes, wherein determining the second hash map associated with the first key from among the plurality of hash maps comprises: hashing the first key to produce a hashed key; obtaining a first hash map that maps a set of hashed keys to the plurality of hash maps, the first hash map being configured to be loaded into on-board memory of one of said nodes; inputting the hashed key into the first hash map; and outputting an identifier of the second hash map corresponding to the hashed key; hashing the first key to produce a hashed key; obtaining a first hash map that maps a set of hashed keys to the plurality of hash maps, the first hash map being configured to be loaded into on-board memory of one of said nodes; inputting the hashed key into the first hash map; and outputting an identifier of the second hash map corresponding to the hashed key; determining an index value associated with a second key using the determined second hash map, wherein utilizing the plurality of hash maps to determine the second hash map associated with the first key enables a lookup to be performed on said second hash map to determine the index value using the on-board memory of the electronic device; and determining transaction processing data associated with the first key using the determined index value, wherein determining transaction processing data associated with the first key using the determined index value comprises: obtaining an indexed list, the indexed list mapping a plurality of index values to a plurality of transaction processing data, the indexed list being stored in a centralized data store of the distributed computing system; inputting the index value into the indexed list; and outputting the transaction processing data corresponding to the index value; and obtaining an indexed list, the indexed list mapping a plurality of index values to a plurality of transaction processing data, the indexed list being stored in a centralized data store of the distributed computing system; inputting the index value into the indexed list; and outputting the transaction processing data corresponding to the index value; and providing the determined transaction processing data, wherein the first key and the second key are the same.